CVE-2026-12891

Description

A flaw was found in the GStreamer gst-plugins-bad package. When processing a malformed H.266/VVC video stream with a crafted aspect ratio indicator value, the H.266 parser performs an out-of-bounds read of up to 8 bytes from adjacent memory. This flaw allows an attacker to craft a malicious H.266 video file or stream that, when processed by a GStreamer-based application, could leak limited memory contents through video metadata, potentially exposing sensitive information from the application's address space.

Statement

Red Hat Enterprise Linux versions that ship gstreamer1-plugins-bad with H.266/VVC parser support are affected by this vulnerability. The impact is rated Moderate because exploitation requires user interaction (opening or streaming a malicious H.266 media file) and the information disclosure is limited to 8 bytes from the read-only .data section per malformed frame, making it difficult to extract meaningful sensitive data in practice. The vulnerability does not lead to code execution or denial of service under normal circumstances. Versions of gstreamer1-plugins-bad that do not include H.266/VVC parser support (typically older releases before the H.266 codec was added) are not affected by this specific vulnerability.

Mitigation

No mitigation is currently available that meets Red Hat Product Security's standards for usability, deployment, applicability, or stability.

Common Vulnerability Scoring System (CVSS) Score Details

Info alert:Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score4.3N/A4.3
Attack VectorNetworkN/ANetwork
Attack ComplexityLowN/ALow
Privileges RequiredNoneN/ANone
User InteractionRequiredN/ARequired
ScopeUnchangedN/AUnchanged
ConfidentialityLowN/ALow
Integrity ImpactNoneN/ANone
Availability ImpactNoneN/ANone

Vector

Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N

cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N

Red Hat CVSS v3 Score Explanation

Network-delivered malicious H.266 stream causes limited .data section information disclosure via OOB read; user interaction required, no code execution or DoS

Understanding the Weakness (CWE)

Confidentiality

Technical Impact: Read Memory

An attacker could get secret values such as cryptographic keys, PII, memory addresses, or other information that could be used in additional attacks.

Confidentiality

Technical Impact: Bypass Protection Mechanism

Out-of-bounds memory could contain memory addresses or other information that can be used to bypass ASLR and other protection mechanisms in order to improve the reliability of exploiting a separate weakness for code execution.

Availability

Technical Impact: DoS: Crash, Exit, or Restart

An attacker could cause a segmentation fault or crash by causing memory to be read outside of the bounds of the buffer. This is especially likely when the code reads a variable amount of data and assumes that a sentinel exists to stop the read operation, such as a NUL in a string.

Other

Technical Impact: Varies by Context

The read operation could produce other undefined or unexpected results.

Acknowledgements

Red Hat would like to thank Dr. Faruk Kazi (CoE-CNDS Lab, VJTI, Mumbai, India) and Ramesh Adhikari (CoE-CNDS Lab, VJTI, Mumbai, India) for reporting this issue.

Frequently Asked Questions

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