8.6

CVE-2025-27091

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)
Daten sind bereitgestellt durch National Vulnerability Database (NVD)
Cisco ≫ Openh264 Version < 2.5.1
Zu dieser CVE wurde keine CISA KEV oder CERT.AT-Warnung gefunden.
EPSS Metriken
Typ Quelle Score Percentile
EPSS FIRST.org 0.37% 0.584
CVSS Metriken
Quelle Base Score Exploit Score Impact Score Vector String
nvd@nist.gov 7.5 1.6 5.9
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
security-advisories@github.com 8.6 0 0
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/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
CWE-122 Heap-based Buffer Overflow

A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().

CWE-787 Out-of-bounds Write

The product writes data past the end, or before the beginning, of the intended buffer.