4.8
MEDIUM CVSS 4.0
CVE-2026-125175
FFmpeg through 9.0.2 Information Disclosure via Flash Screen Video Decoder
Description

FFmpeg through 9.0.2 contains an information disclosure vulnerability in flashsv_decode_block() in libavcodec/flashsv.c that copies uninitialized heap memory into decoded frames when inflate output is short. Attackers can supply a crafted FLV with an FSV1 stream whose zlib block data decompresses short, then recover heap contents from the decoded or re-encoded 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-2026-125175 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 later than 9.0.2 to fix heap memory disclosure.
  • Update FFmpeg to a version later than 9.0.2.
  • Avoid processing untrusted FLV files if update is not possible.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-125175 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-2026-125175 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-2026-125175 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-125175 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 flashsv_decode_block() in libavcodec/flashsv.c that copies uninitialized heap memory into decoded frames when inflate output is short. Attackers can supply a crafted FLV with an FSV1 stream whose zlib block data decompresses short, then recover heap contents from the decoded or re-encoded 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-2026-125175.json">CVE-2026-125175</a>
    Added Reference https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/24464
    Added Reference https://github.com/FFmpeg/FFmpeg
    Added Reference https://github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/flashsv.c#L248
    Added Reference https://github.com/FFmpeg/FFmpeg/commit/50d206a75b5e60261d71b25657ae04891eb60290
    Added Reference https://github.com/FFmpeg/FFmpeg/commit/cfb40c912927fdd2c1186b7b6aca468422da23db
    Added Reference https://www.vulncheck.com/advisories/ffmpeg-through-9.0.2-information-disclosure-via-flash-screen-video-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.