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TI-2026-21194 Aliases CVE-2026-26203

PJSIP's pjmedia-video has use-after-free in H264 packetizer when packetizing fragmented NAL

Priority LOW 22CWE-416Published · Updated

Key facts

Attack vector
Local
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
—
Confidentiality · integrity · availability
None · None · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA.

Summary

PJSIP is a free and open source multimedia communication library. Versions prior to 2.17 have a critical heap buffer underflow vulnerability in PJSIP's H.264 packetizer. The bug occurs when processing malformed H.264 bitstreams without NAL unit start codes, where the packetizer performs unchecked pointer arithmetic that can read from memory located before the allocated buffer. Version 2.17 contains a patch for the issue.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00118 1st percentileScored 2026-11-07
Fix Fixed pjmedia-video (pjsip): 2.17

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
pjsippjmedia-videobefore 2.172.17Patch availableCNA
  • pjmedia-video Vendorpjsip Affected before 2.17 Fixed in 2.17 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:pjsip:pjsip:*:*:*:*:*:*:*:*before 2.17Vulnerablepjsip
  • cpe:2.3:a:pjsip:pjsip:*:*:*:*:*:*:*:* Versions before 2.17 Vulnerable ·pjsip

Remediation

  • Fix · CNA pjmedia-video (pjsip) Fixed in 2.17

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-26203

References

  • TI-2022-08599 Potential out-of-bound read/write in PJSIP CVSS 3.1CRITICAL 9.8
  • TI-2026-21009 PJSIP has a heap buffer overflow in ICE with long username CVSS 4.0HIGH 8.1
  • TI-2022-18621 Buffer overflow in pjlib scanner and pjmedia CVSS 3.1CRITICAL 9.8
  • TI-2026-29548 PJSIP: Stack buffer overflow in pjsip_auth_create_digest2() CVSS 4.0HIGH 8.1
  • TI-2026-23213 PJSIP: Stack buffer overflow in Opus codec parser CVSS 4.0HIGH 8.7
  • TI-2026-22993 PJSIP: Heap use-after-free in PJSIP presence subscription termination handler CVSS 4.0HIGH 8.7
See all 13 →

Sources