Denial of Service Vulnerability in OpenSIPS SIP Server Implementation
CVE-2026-46334
What is CVE-2026-46334?
In OpenSIPS, a Session Initiation Protocol (SIP) server, a vulnerability has been identified in the parsing logic of the Session Description Protocol (SDP) bandwidth line. If an attacker sends a SIP request with a malformed SDP bandwidth line that lacks the necessary colon delimiter and specifies Content-Type: application/sdp, it can lead to corrupted SDP metadata. This corruption may cause the OpenSIPS worker process to crash when subsequent operations—such as dialog handling or Quality of Service (QoS) processing—attempt to utilize the faulty SDP state. An unauthenticated remote attacker can exploit this issue in any system configuration that processes attacker-controlled SDP, resulting in potential service disruption. The flaw has been rectified in versions 3.6.6 and 4.0.0-rc1.
Affected Version(s)
opensips >= 3.4.0, < 3.6.6 < 3.4.0, 3.6.6
opensips >= 4.0.0-beta, < 4.0.0-rc1 < 4.0.0-beta, 4.0.0-rc1