CVE-2026-84975Disclosure(teluu / pjsip)

LOWCVSS 7.4 · HIGH

Signal is active with 1 mentions in latest observed window

Immediate actions

  • Patch teluu pjsip systems immediately

Recommended action window: Monitor and triage in normal cycle

NVD 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.

0.5/ 10 priority

Sources & remediation

Weakness type (CWE)
CWE-295CWE-297

Priority

LOW

Exploitation

NONE

PoC

NONE

Patch

AVAILABLE

Momentum

NONE

Are you affected?

If you run products in this scope, you should treat this CVE as relevant to your environment.

  • pjsip

Threat summary

  • Patch or workaround signal is available
  • 1 mentions across 1 observed day

What's happening

  • Patch or workaround mentioned in 1 signal
  • Technical details provided in 1 signal
  • Disclosure: 1 classified signal
  • 1 total mentions across 1 day

Affected systems

Vendors
Products
pjsip

Deep dive

Activity timeline1 mentions / 1d
00111Mentions · 2026-09-20: 1Patch / Workaround · 2026-09-20: 1Technical Details · 2026-09-20: 109-20
Signal classification1 categories
Disclosure
1100.0%
Referenced assets1 URL
By indicator
Full discourse1 post
  • Hugo | DevOps | Cybersecurity 🇱🇻@HugoValters
    Disclosure

    CVE-2026-84975 PJSIP 2.17 and earlier: NUL byte truncation in TLS cert SAN handling weakens server verification, enabling MITM. CVSS 7.4. No patch yet - restrict TLS/SIPS or verify certs out of band. https://www.valtersit.com/cve/CVE-2026-84975/ #CVE #infosec #PJSIP #PJSIP #CVEALERT #CVE #infosec #Linux #XSS #valtersit #snippet #SysAdmin #cybersecurity #devsecops #devops #developer #100daysofcode #git #github #gitlab #redteam #blueteam #ethicalhacker #cybersecurityawareness #cybersecuritynews #cybersecuritytips #python #hacker #kali #ubuntu #debian #docker

    Post summary

    Post announces CVE-2026-84975 in PJSIP <=2.17 with technical details (NUL byte truncation, MITM, CVSS 7.4) and interim workaround; no patch or PoC is mentioned.

    0001051
    1.1K followersView on X
CPE platform detail1 entries

1 of 1 entries

PartVendorProductVersionTarget SWTarget HW
Appteluupjsip---

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