Author: Ameeba

Overview

The Official Document Management System developed by 2100 Technology was found to have a severe security flaw, identified as CVE-2025-8853. This vulnerability allows an unauthenticated remote attacker to bypass the system’s authentication mechanism, obtain any user’s connection token, and subsequently log into the system as that user. This flaw affects all users and systems that utilize this Document Management System, posing a significant threat to data security. Given the severity of the impact, which includes potential system compromise and data leakage, it’s essential to understand and rectify this vulnerability promptly.

Vulnerability Summary

CVE ID: CVE-2025-8853
Severity: Critical (9.8 CVSS Score)
Attack Vector: Network
Privileges Required: None
User Interaction: None
Impact: System compromise and data leakage

Affected Products

Product | Affected Versions

Official Document Management System | All versions up to the most recent

How the Exploit Works

The vulnerability lies in the authentication mechanism of the Official Document Management System. An unauthenticated remote attacker can craft network requests that spoof the system into disclosing user authentication tokens. Once such a token is obtained, the attacker can use it to authenticate themselves as the user associated with the token, gaining the same rights and permissions as the compromised user.

Conceptual Example Code

To illustrate, an attacker might construct an HTTP request like the one below:

GET /api/v1/auth/tokens HTTP/1.1
Host: target.example.com
User-Agent: any_browser_user_agent_string

In response to this request, the system might return an authentication token that the attacker could use to authenticate as a user:

HTTP/1.1 200 OK
Content-Type: application/json
{
"auth_token": "compromised_user_token"
}

With this token, the attacker can now authenticate as the compromised user and potentially perform any actions this user is authorized to perform.

Mitigation

The best course of action to mitigate this vulnerability is to apply the official patch provided by 2100 Technology. In cases where applying the patch is not immediately feasible, implementing a Web Application Firewall (WAF) or Intrusion Detection System (IDS) can provide temporary mitigation by detecting and blocking malicious requests that attempt to exploit this vulnerability. However, these are only temporary solutions and do not address the root cause of the vulnerability. It’s crucial to install the vendor-provided patch as soon as possible to fully resolve the issue.

Overview

The CVE-2025-8831 is a critical vulnerability found in a selection of Linksys Wi-Fi Extenders models. The vulnerability is located in the function remoteManagement of the file /goform/remoteManagement. The exploitation of this vulnerability can lead to a stack-based buffer overflow, compromising the system and potentially leading to data leakage. The significance of this vulnerability is further elevated by the fact that it can be attacked remotely, and the exploit has been publicly disclosed. Despite being notified of the vulnerability, the vendor has not responded with a patch or workaround.

Vulnerability Summary

CVE ID: CVE-2025-8831
Severity: Critical, CVSS Severity Score 8.8
Attack Vector: Network
Privileges Required: None
User Interaction: None
Impact: Potential system compromise and data leakage

Affected Products

Product | Affected Versions

Linksys RE6250 | Up to 20250801
Linksys RE6300 | Up to 20250801
Linksys RE6350 | Up to 20250801
Linksys RE6500 | Up to 20250801
Linksys RE7000 | Up to 20250801
Linksys RE9000 | Up to 20250801

How the Exploit Works

The exploit works by manipulating the argument portNumber in the remoteManagement function of the file /goform/remoteManagement. This manipulation causes a stack-based buffer overflow which compromises the system. An attacker can initiate this exploit remotely, which increases its potential impact.

Conceptual Example Code

A conceptual example of this exploit could be an HTTP request like this:

POST /goform/remoteManagement HTTP/1.1
Host: target.example.com
Content-Type: application/x-www-form-urlencoded
portNumber=65536  //This is a conceptual example and the actual malicious payload may vary

In this example, an excessively large portNumber is sent, which the system may not be prepared to handle, leading to a buffer overflow.

Mitigation Guidance

As the vendor has not provided a patch or workaround, it is highly recommended to apply a third-party patch if available or implement a Web Application Firewall (WAF) or Intrusion Detection System (IDS) as a temporary mitigation measure. Additionally, frequent monitoring and logging of the network activities can help detect any unusual activities early on.

Overview

A critical vulnerability, identified as CVE-2025-8826, has been discovered in multiple models of Linksys wireless range extenders. This vulnerability, if successfully exploited, could potentially compromise the system or lead to data leakage. This vulnerability affects a significant number of users globally, given the wide usage of Linksys devices. The urgency of this situation is further escalated due to the existence of a public disclosure of the exploit.

Vulnerability Summary

CVE ID: CVE-2025-8826
Severity: Critical (CVSS: 8.8)
Attack Vector: Remote
Privileges Required: None
User Interaction: None
Impact: Potential system compromise or data leakage

Affected Products

Product | Affected Versions

Linksys RE6250 | Up to 20250801
Linksys RE6300 | Up to 20250801
Linksys RE6350 | Up to 20250801
Linksys RE6500 | Up to 20250801
Linksys RE7000 | Up to 20250801
Linksys RE9000 | Up to 20250801

How the Exploit Works

The vulnerability resides in the function um_rp_autochannel of the file /goform/RP_setBasicAuto. The manipulation of the argument apcli_AuthMode_2G/apcli_AuthMode_5G can trigger a stack-based buffer overflow. This is due to the software failing to properly handle inputs before storing them in a buffer, leading to a memory corruption and potential execution of arbitrary code.

Conceptual Example Code

An example of how this vulnerability might be exploited could look like this:

POST /goform/RP_setBasicAuto HTTP/1.1
Host: vulnerable-device-ip
Content-Type: application/x-www-form-urlencoded
apcli_AuthMode_2G=AAAAAAAAAA...[long string of A's]...AAAAAAAAAAAA

In this hypothetical example, the attacker sends an HTTP POST request to the /goform/RP_setBasicAuto endpoint with a specially crafted ‘apcli_AuthMode_2G’ parameter. This long string of “A”s is designed to overflow the buffer and potentially execute arbitrary code.

Mitigation

Users of the affected Linksys models are advised to apply the vendor patch as soon as it becomes available. In the interim, using a Web Application Firewall (WAF) or Intrusion Detection System (IDS) can help mitigate the risk. These systems can be configured to identify and block attempts to exploit this vulnerability.

Overview

The cybersecurity landscape has been shaken by the discovery of a critical vulnerability, CVE-2025-8824, affecting a range of Linksys products. This vulnerability may potentially lead to system compromise and data leakage, posing a significant risk to users of the affected models. In particular, it affects the Linksys RE6250, RE6300, RE6350, RE6500, RE7000, and RE9000 up to version 20250801.
The vulnerability lies within the setRIP function of the /goform/setRIP file. If exploited, this vulnerability could potentially enable an attacker to execute arbitrary code on the affected device. The issue is of particular concern as the exploit has been publicly disclosed and remains unpatched by the vendor, despite early notification.

Vulnerability Summary

CVE ID: CVE-2025-8824
Severity: Critical (8.8 CVSS score)
Attack Vector: Network
Privileges Required: None
User Interaction: None
Impact: Potential system compromise or data leakage

Affected Products

Product | Affected Versions

Linksys RE6250 | Up to 20250801
Linksys RE6300 | Up to 20250801
Linksys RE6350 | Up to 20250801
Linksys RE6500 | Up to 20250801
Linksys RE7000 | Up to 20250801
Linksys RE9000 | Up to 20250801

How the Exploit Works

The vulnerability originates from incorrect buffer management within the setRIP function of the /goform/setRIP file. The manipulation of the arguments RIPmode/RIPpasswd can lead to a stack-based buffer overflow. This type of vulnerability typically allows an attacker to overwrite the intended buffer’s boundaries, potentially leading to the execution of arbitrary code.

Conceptual Example Code

A potential exploitation scenario might involve sending a specially crafted HTTP request to the vulnerable endpoint. An example could be:

POST /goform/setRIP HTTP/1.1
Host: target.example.com
Content-Type: application/x-www-form-urlencoded
RIPmode=1&RIPpasswd=A*10000

In this conceptual example, the RIPpasswd parameter is filled with a large number of characters, far exceeding the size of the buffer that the setRIP function has allocated for it. This could potentially lead to a buffer overflow, depending on the specifics of the implementation.

Overview

A significant cybersecurity vulnerability, identified as CVE-2025-8822, has been discovered in multiple models of Linksys devices. This vulnerability has potential for system compromise or data leakage, posing a serious risk to users and organizations using the affected devices. Given that these devices are often used as a backbone for networking infrastructure, the risk presented by this vulnerability is notable.
The vulnerability stems from a stack-based buffer overflow in the function algDisable of the file /goform/setOpMode. This issue allows attackers to manipulate the opMode argument to trigger the overflow, potentially leading to remote code execution or data leakage. The vulnerability has been publicly disclosed and thus, may be exploited by malicious parties.

Vulnerability Summary

CVE ID: CVE-2025-8822
Severity: High (8.8 CVSS Score)
Attack Vector: Network
Privileges Required: None
User Interaction: None
Impact: System compromise or data leakage

Affected Products

Product | Affected Versions

Linksys RE6250 | up to 20250801
Linksys RE6300 | up to 20250801
Linksys RE6350 | up to 20250801
Linksys RE6500 | up to 20250801
Linksys RE7000 | up to 20250801
Linksys RE9000 | up to 20250801

How the Exploit Works

This vulnerability exploits the algDisable function’s handling of input data. By supplying an excessively long argument to the opMode parameter, it is possible to cause a stack-based buffer overflow. This overflow can corrupt memory and potentially lead to arbitrary code execution, allowing the attacker to gain control over the system. The vulnerability is remotely exploitable, meaning an attacker does not need physical access to the device to exploit this vulnerability; they only need network access.

Conceptual Example Code

While the exact exploit code has not been disclosed, an example of how the vulnerability might be exploited could look like this:

POST /goform/setOpMode HTTP/1.1
Host: vulnerable-linksys-device
Content-Type: application/x-www-form-urlencoded
opMode=AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA...

In this example, the ‘A’s represent an excessively long string that would trigger the buffer overflow. The attacker would need to craft a string of the correct length, possibly containing specific bytes to exploit this vulnerability successfully.

Overview

A significant cybersecurity threat has been discovered targeting a range of Linksys range extenders, namely the RE6250, RE6300, RE6350, RE6500, RE7000, and RE9000 models. The vulnerability, identified as CVE-2025-8820, poses a serious risk to the integrity and confidentiality of data, as well as the availability of systems using these devices. This threat is especially concerning due to its high severity score and the fact that the exploit has been publicly disclosed, with potential for wide-ranging misuse.

Vulnerability Summary

CVE ID: CVE-2025-8820
Severity: Critical (8.8/10)
Attack Vector: Network
Privileges Required: None
User Interaction: None
Impact: Potential system compromise or data leakage

Affected Products

Product | Affected Versions

Linksys RE6250 | up to 20250801
Linksys RE6300 | up to 20250801
Linksys RE6350 | up to 20250801
Linksys RE6500 | up to 20250801
Linksys RE7000 | up to 20250801
Linksys RE9000 | up to 20250801

How the Exploit Works

The vulnerability exists due to a stack-based buffer overflow in the wirelessBasic function of the /goform/wirelessBasic file. By manipulating the argument submit_SSID1, an attacker can cause an overflow of the buffer, which can lead to execution of arbitrary code on the system. This exploit can be triggered remotely, and it does not require any user interaction or special privileges, making it particularly dangerous.

Conceptual Example Code

While the specific exploit code has not been disclosed, the conceptual example given below shows how an HTTP request might be able to exploit the vulnerability:
“`http
POST /goform/wirelessBasic HTTP/1.1
Host: target.example.com
Content-Type: application/x-www-form-urlencoded
submit_SSID1=AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA

Overview

CVE-2025-8819 is a serious vulnerability that has been identified in various models of Linksys devices. The affected devices include RE6250, RE6300, RE6350, RE6500, RE7000, and RE9000. This vulnerability resides in the setWan function of the /goform/setWan file, enabling potential system compromise or data leakage. The vulnerability is significant due to the potential for remote exploitation. The exploit has been made public, heightening the urgency for users and administrators to apply mitigation measures.

Vulnerability Summary

CVE ID: CVE-2025-8819
Severity: Critical (CVSS: 8.8)
Attack Vector: Network
Privileges Required: None
User Interaction: None
Impact: System compromise, potential data leakage

Affected Products

Product | Affected Versions

Linksys RE6250 | up to 20250801
Linksys RE6300 | up to 20250801
Linksys RE6350 | up to 20250801
Linksys RE6500 | up to 20250801
Linksys RE7000 | up to 20250801
Linksys RE9000 | up to 20250801

How the Exploit Works

The vulnerability lies in the manipulation of the ‘staticIp’ argument within the setWan function. An attacker can remotely send a specially crafted request to the vulnerable function, causing a stack-based buffer overflow. This overflow can lead to a denial of service or allow an attacker to execute arbitrary code on the compromised system.

Conceptual Example Code

The following is a conceptual example of how the vulnerability might be exploited. Note that this is a theoretical example and does not represent actual exploit code.

POST /goform/setWan HTTP/1.1
Host: target.example.com
Content-Type: application/x-www-form-urlencoded
staticIp=AAAA...[long string of A's to overflow buffer]

The attacker sends a POST request with a long string of characters as the ‘staticIp’ parameter. This string overflows the buffer, causing the buffer overflow vulnerability.

Countermeasures

The best mitigation strategy is to apply the vendor’s patch, which should eliminate the vulnerability. If the vendor patch is not available or cannot be applied immediately, a temporary solution could be to use a Web Application Firewall (WAF) or an Intrusion Detection System (IDS) to block malicious requests targeting this vulnerability. However, these are only temporary solutions and do not fully mitigate the risk. The ultimate solution is to apply the vendor patch as soon as it becomes available.

Overview

The CVE-2025-8817 vulnerability, identified in a range of Linksys devices, presents a serious threat to data security and system integrity. This vulnerability affects Linksys RE6250, RE6300, RE6350, RE6500, RE7000, and RE9000 devices up to version 20250801. The vulnerability, which lies in the functionality of the setLan file, can be exploited remotely, potentially leading to system compromise or data leakage. The severity of this vulnerability underscores the need for immediate action from both users and the vendor.

Vulnerability Summary

CVE ID: CVE-2025-8817
Severity: Critical (CVSS: 8.8)
Attack Vector: Remote
Privileges Required: None
User Interaction: None
Impact: Potential system compromise or data leakage

Affected Products

Product | Affected Versions

Linksys RE6250 | Up to 20250801
Linksys RE6300 | Up to 20250801
Linksys RE6350 | Up to 20250801
Linksys RE6500 | Up to 20250801
Linksys RE7000 | Up to 20250801
Linksys RE9000 | Up to 20250801

How the Exploit Works

The vulnerability stems from a stack-based buffer overflow in the setLan function of the /goform/setLan file in the affected Linksys devices. This is triggered by the improper handling of the lan2enabled argument, which can be manipulated to overflow the buffer. This overflow can lead to arbitrary code execution, allowing an attacker to compromise the system or leak data.

Conceptual Example Code

Here’s a conceptual example of how an HTTP request exploiting this vulnerability might look:

POST /goform/setLan HTTP/1.1
Host: target_linksys_device
Content-Type: application/x-www-form-urlencoded
lan2enabled=1&lan2ipAddr=192.168.1.1&lan2SubnetMask=255.255.255.0&lan2DhcpStart=192.168.1.100&lan2DhcpEnd=192.168.1.150&lan2DhcpEnabled=1&lan2Dns1=192.168.1.1&lan2Lease=86400&lan2Domain=&lan2Gateway=192.168.1.1&lan2Dns2=192.168.1.1&lan2Dns3=192.168.1.1&lan2enabled=A*50000

In the above code, the lan2enabled parameter is filled with “A*50000” which is significantly larger than what the system is designed to handle, leading to a buffer overflow.
It’s important to note that the above is a simplified example and actual exploitation may require more complex manipulation.

Mitigation

As a short-term mitigation, users are advised to use a Web Application Firewall (WAF) or Intrusion Detection System (IDS). However, the ultimate solution is the application of a vendor patch. Despite contacting the vendor about this critical disclosure, they have yet to respond. Users should stay abreast of any updates from the vendor and apply patches as soon as they become available.

Overview

A critical vulnerability, identified as CVE-2025-8816, has been identified in several models of Linksys range extenders. This vulnerability is present in the setOpMode function of the /goform/setOpMode file, which can lead to a stack-based buffer overflow when manipulated via the argument ‘ethConv’. This vulnerability poses a significant threat due to its potential to compromise systems or leak data. The issue affects a wide array of Linksys devices, thereby posing a risk to a large number of users worldwide.
The vulnerability is particularly concerning as it can be exploited remotely, and the details of the exploit have been publicly disclosed. Despite being notified, the vendor has not responded to this disclosure, increasing the urgency of addressing this vulnerability.

Vulnerability Summary

CVE ID: CVE-2025-8816
Severity: Critical (8.8 CVSS 3.x Severity Score)
Attack Vector: Network
Privileges Required: None
User Interaction: None
Impact: Potential system compromise or data leakage

Affected Products

Product | Affected Versions

Linksys RE6250 | up to 20250801
Linksys RE6300 | up to 20250801
Linksys RE6350 | up to 20250801
Linksys RE6500 | up to 20250801
Linksys RE7000 | up to 20250801
Linksys RE9000 | up to 20250801

How the Exploit Works

The vulnerability lies in the setOpMode function of the /goform/setOpMode file. An attacker can manipulate the ‘ethConv’ argument to trigger a buffer overflow. Buffer overflow occurs when more data is put into a buffer than it can handle, causing it to overwrite adjacent memory areas, leading to erratic program behavior, including memory access errors, incorrect results, program termination, or a breach of system security.

Conceptual Example Code

The following is a conceptual example of how the vulnerability might be exploited using an HTTP POST request to the vulnerable endpoint:

POST /goform/setOpMode HTTP/1.1
Host: target.example.com
Content-Type: application/x-www-form-urlencoded
ethConv=AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA...

In this example, the ‘ethConv’ argument is filled with an excessively long string of ‘A’ characters, causing a buffer overflow and potentially allowing for the execution of malicious code.

Overview

Cybersecurity enthusiasts and professionals alike need to be aware of a recently discovered and publicly disclosed vulnerability, CVE-2025-8810, within the Tenda AC20 16.03.08.05. This vulnerability, classified as critical, affects the strcpy function of the file /goform/SetFirewallCfg through the manipulation of the argument firewallEn, leading to a stack-based buffer overflow. Given the critical nature of this exploit, it has the potential to compromise systems or leak sensitive data, creating a significant risk for organizations and individuals utilizing the affected product. The bug is particularly concerning as it can be launched remotely, thus amplifying its potential damage.

Vulnerability Summary

CVE ID: CVE-2025-8810
Severity: Critical (CVSS: 8.8)
Attack Vector: Remote
Privileges Required: None
User Interaction: Not required
Impact: Potential system compromise or data leakage

Affected Products

Product | Affected Versions

Tenda AC20 | 16.03.08.05

How the Exploit Works

The exploit works by taking advantage of a stack-based buffer overflow vulnerability in the strcpy function of the /goform/SetFirewallCfg file in the Tenda AC20 router firmware. An attacker can maliciously manipulate the argument ‘firewallEn’ to overflow the buffer, which can potentially lead to arbitrary code execution. This means that the attacker can perform any operation on the system, leading to a complete system compromise or data leakage.

Conceptual Example Code

Here is a conceptual example of how the vulnerability might be exploited. This example assumes the attacker sends a malicious HTTP POST request to the vulnerable endpoint:

POST /goform/SetFirewallCfg HTTP/1.1
Host: target.example.com
Content-Type: application/x-www-form-urlencoded
firewallEn=1&buffer=[Insert malicious payload here]

In this example, ‘[Insert malicious payload here] would be replaced with a payload designed to overflow the buffer, potentially leading to arbitrary code execution.

Mitigation

To mitigate this vulnerability, it is recommended to apply the vendor patch as soon as it becomes available. In the meantime, using a Web Application Firewall (WAF) or Intrusion Detection System (IDS) can serve as a temporary mitigation strategy, helping to identify and block potential exploit attempts.