4.8
MEDIUM CVSS 4.0
CVE-2026-125177
FFmpeg through 9.0.2 Uninitialized Heap Memory Disclosure via MSCC/SRGC Decoder
Description

FFmpeg through 9.0.2 contains an information disclosure vulnerability in the MSCC/SRGC decoder in libavcodec/mscc.c that outputs uninitialized heap bytes when RLE data ends early. Attackers can craft an MSCC or SRGC stream, such as in AVI, whose RLE data terminates early so the decoded frame exposes leftover heap memory to viewers of the output.

INFO

Published Date :

Nov. 9, 2026, 7:16 p.m.

Last Modified :

Nov. 9, 2026, 7:16 p.m.

Remotely Exploit :

No
Affected Products

The following products are affected by CVE-2026-125177 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Ffmpeg ffmpeg
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 LOW 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 3.1 LOW [email protected]
CVSS 4.0 MEDIUM 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 4.0 MEDIUM [email protected]
Solution
Update FFmpeg to a version that addresses the heap data disclosure in the MSCC/SRGC decoder.
  • Update FFmpeg to a version newer than 9.0.2.
  • Apply vendor patches for the MSCC/SRGC decoder.
  • Validate RLE data termination in streams.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-125177 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-125177 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-125177 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-125177 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Nov. 09, 2026

    Action Type Old Value New Value
    Added Description FFmpeg through 9.0.2 contains an information disclosure vulnerability in the MSCC/SRGC decoder in libavcodec/mscc.c that outputs uninitialized heap bytes when RLE data ends early. Attackers can craft an MSCC or SRGC stream, such as in AVI, whose RLE data terminates early so the decoded frame exposes leftover heap memory to viewers of the output.
    Added CVSS V4.0 AV:L/AC:L/AT:N/PR:N/UI:P/VC:L/VI:N/VA:N/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
    Added CVSS V3.1 AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
    Added CWE CWE-908
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/125xxx/CVE-2026-125177.json">CVE-2026-125177</a>
    Added Reference https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/24465
    Added Reference https://github.com/FFmpeg/FFmpeg
    Added Reference https://github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/mscc.c#L236
    Added Reference https://github.com/FFmpeg/FFmpeg/commit/263a85e2a2127396f8a2b0c329ec798e1ea015ad
    Added Reference https://www.vulncheck.com/advisories/ffmpeg-through-9.0.2-uninitialized-heap-memory-disclosure-via-mscc-srgc-decoder
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.