Improper Certificate Validation in pjsip - #VU127457
Published: April 24, 2026
Vulnerability identifier: #VU127457
CSH Severity: High
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Amber
CVE-ID: N/A
CWE-ID: CWE-295
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: pjsip
Affected software:
pjsip
pjsip
Detailed vulnerability description
The vulnerability allows a remote attacker to perform a man-in-the-middle attack on outbound sips connections.
The vulnerability exists due to improper certificate validation in sip_transport_tls when handling tls handshakes on GnuTLS builds with verify_server enabled. A remote attacker can present an untrusted, expired, or self-signed certificate to perform a man-in-the-middle attack on outbound sips connections.
Only GnuTLS builds configured with --with-gnutls are vulnerable.
Remediation
Install security update from vendor's website.