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CVE-2025-27091 Detail

Description

OpenH264 is a free license codec library which supports H.264 encoding and decoding. A vulnerability in the decoding functions of OpenH264 codec library could allow a remote, unauthenticated attacker to trigger a heap overflow. This vulnerability is due to a race condition between a Sequence Parameter Set (SPS) memory allocation and a subsequent non Instantaneous Decoder Refresh (non-IDR) Network Abstraction Layer (NAL) unit memory usage. An attacker could exploit this vulnerability by crafting a malicious bitstream and tricking a victim user into processing an arbitrary video containing the malicious bistream. An exploit could allow the attacker to cause an unexpected crash in the victim's user decoding client and, possibly, perform arbitrary commands on the victim's host by abusing the heap overflow. This vulnerability affects OpenH264 2.5.0 and earlier releases. Both Scalable Video Coding (SVC) mode and Advanced Video Coding (AVC) mode are affected by this vulnerability. OpenH264 software releases 2.6.0 and later contained the fix for this vulnerability. Users are advised to upgrade. There are no known workarounds for this vulnerability. ### For more information If you have any questions or comments about this advisory: * [Open an issue in cisco/openh264](https://github.com/cisco/openh264/issues) * Email Cisco Open Source Security ([oss-security@cisco.com](mailto:oss-security@cisco.com)) and Cisco PSIRT ([psirt@cisco.com](mailto:psirt@cisco.com)) ### Credits: * **Research:** Octavian Guzu and Andrew Calvano of Meta * **Fix ideation:** Philipp Hancke and Shyam Sadhwani of Meta * **Fix implementation:** Benzheng Zhang (@BenzhengZhang) * **Release engineering:** Benzheng Zhang (@BenzhengZhang)


Metrics

NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

Nist CVSS score does not match with CNA score
CNA:  GitHub, Inc.
CVSS-B 8.6 HIGH
Vector:  CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

References to Advisories, Solutions, and Tools

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Hyperlink Resource
https://github.com/cisco/openh264/releases/tag/v2.6.0 Release Notes 
https://github.com/cisco/openh264/security/advisories/GHSA-m99q-5j7x-7m9x Vendor Advisory 

Weakness Enumeration

CWE-ID CWE Name Source
CWE-787 Out-of-bounds Write cwe source acceptance level NIST  
CWE-122 Heap-based Buffer Overflow GitHub, Inc.  

Known Affected Software Configurations Switch to CPE 2.2

Configuration 1 ( hide )
 cpe:2.3:a:cisco:openh264:*:*:*:*:*:*:*:*
   Show Matching CPE(s)
Up to (excluding)
2.6.0

Denotes Vulnerable Software
Are we missing a CPE here? Please let us know.

Change History

2 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2025-27091
NVD Published Date:
02/20/2025
NVD Last Modified:
02/27/2025
Source:
GitHub, Inc.