Bug 2441087 (CVE-2026-26203)

Summary: CVE-2026-26203 pjsip: PJSIP: Denial of Service via malformed H.264 bitstream processing
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in PJSIP, a free and open-source multimedia communication library. An attacker could exploit a heap buffer underflow vulnerability by sending specially crafted, malformed H.264 bitstreams without NAL unit start codes. This unchecked pointer arithmetic can cause the packetizer to read from memory before the allocated buffer, leading to a denial of service.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 2441205, 2441206, 2441207    
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Description OSIDB Bzimport 2026-02-19 20:05:37 UTC
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.