Overview
The vulnerability identified as CVE-2025-9527 is a severe flaw in the Linksys E1700 1.0.0.4.003 router, primarily affecting the QoSSetup function. This vulnerability is of significant concern as it exposes the system to remote attacks, enabling potential unauthorized access, system compromise, and data leakage. The exploit has been made public, indicating that any malicious actor with knowledge of the vulnerability can exploit it, escalating the urgency of immediate mitigation.
Vulnerability Summary
CVE ID: CVE-2025-9527
Severity: High (8.8 CVSS Score)
Attack Vector: Network
Privileges Required: None
User Interaction: None
Impact: Potential system compromise and data leakage
Affected Products
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Product | Affected Versions
Linksys E1700 | 1.0.0.4.003
How the Exploit Works
The vulnerability resides in the QoSSetup function of the file /goform/QoSSetup. It arises due to improper handling of the ‘ack_policy’ argument. By manipulating this argument, an attacker can cause a stack-based buffer overflow. This overflow can lead to arbitrary code execution, thus allowing the attacker to compromise the system remotely.
Conceptual Example Code
The following conceptual example demonstrates how an attacker might exploit this vulnerability. This pseudocode represents a malicious HTTP request to the vulnerable endpoint:
POST /goform/QoSSetup HTTP/1.1
Host: target.example.com
Content-Type: application/x-www-form-urlencoded
ack_policy=AAAA...[long string of "A"s to trigger the buffer overflow]Mitigation Guidance
Affected users are strongly advised to apply the vendor patch as soon as it is available. Until then, a Web Application Firewall (WAF) or Intrusion Detection System (IDS) can be used as a temporary mitigation measure to detect and block potential exploitation attempts.
