CVE-2026-84975
Received
Received - Intake
BaseFortify
Vulnerability report for CVE-2026-84975, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-09-18
Last updated on: 2026-09-18
Assigner: GitHub, Inc.
Description
Description
PJSIP is a free and open source multimedia communication library written in C. In 2.17 and earlier, the OpenSSL and GnuTLS backends in pjlib/src/pj/ssl_sock_ossl.c and pjlib/src/pj/ssl_sock_gtls.c copy DNS SubjectAltName values with string functions that recalculate their length and truncate an embedded NUL byte. With server verification enabled through --tls-verify-server for the PJSIP TLS/SIPS transport, a certificate containing a DNS SubjectAltName formed from the target hostname prefix followed by an embedded NUL and an attacker-controlled suffix can therefore be accepted for the prefix hostname. An attacker who possesses such a certificate from a trusted issuer and can intercept the connection can impersonate the target server, complete the SIP session, and receive REGISTER credentials. The mbedTLS backend is not affected because it preserves the explicit string length. No fixed version is available as of this review.
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
Currently, no data is known.
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-297 | The product communicates with a host that provides a certificate, but the product does not properly ensure that the certificate is actually associated with that host. |
| CWE-295 | The product does not validate, or incorrectly validates, a certificate. |
