CVE-2026-57163PJSIP: Stack overflow parsing a TLS peer certificate's SubjectAltName in GnuTLS backend

Official description

PJSIP is a free and open source multimedia communication library written in C. Prior to commit c4a151a, a stack buffer overflow exists in the GnuTLS TLS backend when parsing the Subject Alternative Name extension of a peer certificate (tls_cert_get_info() in ssl_sock_gtls.c). Only GnuTLS builds are affected (--with-gnutls); OpenSSL and Apple SecureTransport/Network.framework builds are not affected. While extracting certificate information after a TLS handshake, an incorrect buffer-size value can cause an oversized SubjectAltName entry to be written past the end of a fixed-size stack buffer. A network-positioned attacker presenting a crafted certificate — a malicious server to a connecting client, or a malicious client to a server that requests certificates — can trigger this during the TLS handshake, before any SIP-level authentication. Impact may range from unexpected application termination to control flow hijack/memory corruption. This issue has been patched via commit c4a151a.

Affected packages & fixed versions

Affected products (as reported)

References

• https://github.com/pjsip/pjproject/security/advisories/GHSA-jm2j-6rg6-qvwx x_refsource_CONFIRM
• https://github.com/pjsip/pjproject/commit/c4a151af86fadd16d9480b2603eeb2abf4fb4f78 x_refsource_MISC