FFmpeg up to 9.0.2 WebP Decoder libavcodec/webp.c vp8_lossy_decode_alpha uninitialized pointer

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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3.0$0-$5k0.00+

Summaryinfo

A vulnerability labeled as problematic has been found in FFmpeg up to 9.0.2. This affects the function vp8_lossy_decode_alpha of the file libavcodec/webp.c of the component WebP Decoder. The manipulation results in uninitialized pointer. This vulnerability is cataloged as CVE-2026-125098. The attack must be initiated from a local position. There is no exploit available.

Detailsinfo

A vulnerability, which was classified as problematic, was found in FFmpeg up to 9.0.2. Affected is the function vp8_lossy_decode_alpha of the file libavcodec/webp.c of the component WebP Decoder. The manipulation with an unknown input leads to a uninitialized pointer vulnerability. CWE is classifying the issue as CWE-824. The product accesses or uses a pointer that has not been initialized. This is going to have an impact on confidentiality. CVE summarizes:

FFmpeg through 9.0.2 contains an information disclosure vulnerability in vp8_lossy_decode_alpha() in libavcodec/webp.c that leaves alpha plane memory uninitialized for short uncompressed ALPH chunks. Attackers can supply a crafted WebP image whose ALPH chunk is shorter than width * height to disclose stale pixel data from previously decoded frames.

The advisory is available at code.ffmpeg.org. This vulnerability is traded as CVE-2026-125098 since 11/09/2026. The exploitability is told to be easy. Local access is required to approach this attack. Successful exploitation requires user interaction by the victim. Technical details are known, but there is no available exploit.

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

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Productinfo

Type

Name

Version

License

Website

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: 3.0
VulDB Meta Temp Score: 3.0

VulDB Base Score: 2.8
VulDB Temp Score: 2.8
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 3.3
CNA Vector (VulnCheck): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Uninitialized pointer
CWE: CWE-824 / CWE-908
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

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

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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-2026-125098 (🔒)

GCVE (CVE): GCVE-0-2026-125098
GCVE (VulDB): GCVE-100-433254

Entryinfo

Created: 11/09/2026 20:23
Changes: 11/09/2026 20:23 (75)
Complete: 🔍
Cache ID: 216::103

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