VDB-433296 · CVE-2026-125256 · GCVE-0-2026-125256

FFmpeg up to 9.0.2 Huffyuv encoder ff_llvidenc_diff_bytes_rvv heap-based overflow

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
5.9	$0-$5k	0.00+

Summaryinfo

A vulnerability labeled as problematic has been found in FFmpeg up to 9.0.2. The affected element is the function ff_llvidenc_diff_bytes_rvv of the component Huffyuv encoder. The manipulation results in heap-based overflow. This vulnerability is identified as CVE-2026-125256. The attack is only possible with local access. There is not any exploit available.

Detailsinfo

A vulnerability classified as problematic has been found in FFmpeg up to 9.0.2. Affected is the function ff_llvidenc_diff_bytes_rvv of the component Huffyuv encoder. The manipulation with an unknown input leads to a heap-based overflow vulnerability. CWE is classifying the issue as CWE-122. The product writes past the end of a buffer that was allocated on the heap. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

FFmpeg through 9.0.2 contains a heap buffer overflow vulnerability in ff_llvidenc_diff_bytes_rvv() that allows attackers to corrupt heap memory by triggering negative length values in the Huffyuv encoder. Attackers can supply RGB video narrower than 8 or 16 pixels for huffyuv transcoding on RVV-enabled RISC-V builds, causing writes past the encoder's temp buffer.

The advisory is shared for download at code.ffmpeg.org. This vulnerability is traded as CVE-2026-125256 since 11/09/2026. The exploitability is told to be easy. The attack needs to be approached locally. Successful exploitation requires user interaction by the victim. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 11/09/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Type

Multimedia Processing Software

Name

FFmpeg

Version

License

open-source

Website

Product: https://ffmpeg.org/

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 5.9
VulDB Meta Temp Score: 5.9

VulDB Base Score: 4.8
VulDB Temp Score: 4.8
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.0
CNA Vector (VulnCheck): 🔒

CVSSv2info

AV	AC	Au	C	I	A
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💳	💳	💳	💳	💳	💳
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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Heap-based overflow
CWE: CWE-122 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

11/09/2026 Advisory disclosed
11/09/2026 +0 days CVE reserved
11/09/2026 +0 days VulDB entry created
11/09/2026 +0 days VulDB entry last update

Sourcesinfo

Product: ffmpeg.org

Advisory: code.ffmpeg.org
Status: Not defined

CNA: VulnCheck
CVE: CVE-2026-125256 (🔒)

GCVE (CVE): GCVE-0-2026-125256
GCVE (VulDB): GCVE-100-433296

Entryinfo

Created: 11/09/2026 20:35
Changes: 11/09/2026 20:35 (74)
Complete: 🔍
Cache ID: 216::103