CVE-2026-26203

Name: CVE-2026-26203
Creator: NVD / NIST
Published: 2026-02-19T20:25:43.113+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.1/10EPSS 0.10%

Last modified Jun 17, 2026

CVE-2026-26203 is a medium-severity vulnerability rated 5.1/10 on the CVSS scale. 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. EPSS estimates a 0.10% chance of exploitation in the next 30 days.

Description

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.

Metrics

CVSS 3.1

6.5/10

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H

CVSS 4.0

5.1/10

CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

EPSS Probability

0.10%

1.1th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-416

Affected Software

Vendor	Product	Versions
Pjsip	Pjsip	< 2.17

References

https://github.com/pjsip/pjproject/commit/5aee54f09d4f91538d55279d7316591b28fded6cPatch
https://github.com/pjsip/pjproject/security/advisories/GHSA-p965-mf7j-gwv8Patch, Vendor Advisory

Timeline

Published: Feb 19, 2026
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2026-26203?

How severe is CVE-2026-26203?

CVE-2026-26203 has a CVSS score of 5.1/10 (MEDIUM severity). The EPSS model estimates a 0.10% probability of exploitation in the next 30 days.

How do I fix CVE-2026-26203?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2026-26203?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST