CVE-2026-57162

Name of the Vulnerable Software and Affected Versions PJSIP versions prior to commit a1b707c

Description A stack buffer overflow occurs in the SRTP/SDES media transport when processing a=crypto attributes during the Session Description Protocol (SDP) offer/answer process. The issue resides in the sdes encode sdp() function within transport srtp sdes.c. During media negotiation, crypto attributes from a remote SDP are collected into a fixed-size array without boundary checks. A remote peer can trigger this by sending an excessive number of a=crypto attributes in a single media description via an incoming SIP INVITE, which occurs before application-level authentication. This can lead to memory corruption, unexpected application termination, or control flow hijack. Only applications with SRTP enabled using SDES keying are affected.

Recommendations Update PJSIP to the version containing commit a1b707c. As a temporary mitigation, disable SRTP or avoid using SDES keying if not strictly required.