Overview
CVE-2025-21483 is a high-severity vulnerability that poses significant risks to user equipment (UE) involved in the reassembly of Network Abstraction Layer Units (NALUs) from Real-time Transport Protocol (RTP) packets. The issue resides in the memory corruption that occurs when the UE receives an RTP packet from the network during the NALUs reassembly process. Given the high CVSS Severity Score of 9.8, it is crucial for organizations and individuals to understand the potential impact of this vulnerability and take the necessary measures to mitigate its effects.
Vulnerability Summary
CVE ID: CVE-2025-21483
Severity: Critical (9.8 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
UE Devices | All versions prior to patch release
How the Exploit Works
An attacker exploiting the CVE-2025-21483 vulnerability would send a specially crafted RTP packet to a target UE device, during the reassembly of NALUs. The malicious packet causes memory corruption in the targeted device, which could then be exploited to gain unauthorized access to the system or to leak sensitive data.
Conceptual Example Code
The following conceptual sample HTTP request could be used by an attacker to exploit the vulnerability:
POST /send/rtp HTTP/1.1
Host: ue-device.example.com
Content-Type: application/octet-stream
{ "rtp_packet": "malicious_payload" }In the above conceptual example, the `”rtp_packet”` field contains the malicious payload designed to trigger the memory corruption vulnerability. The attacker sends this request to the `/send/rtp` endpoint of the targeted UE device. Upon receipt, the device attempts to reassemble the NALUs from the malicious RTP packet, causing memory corruption and enabling the attacker to potentially compromise the system or leak data.
Mitigation and Vendor Patch
The most effective mitigation for the CVE-2025-21483 vulnerability is to apply the patch released by the vendor. If for some reason the patch cannot be immediately applied, implementing a Web Application Firewall (WAF) or Intrusion Detection System (IDS) can serve as a temporary measure to detect and block exploit attempts. However, these are only stopgap solutions, and the vendor patch should be applied as soon as feasible to fully mitigate the risk.
