FFmpeg up to 9.0.2 JPEG-LS Decoder libavcodec/jpeglsdec.c ff_jpegls_decode_picture uninitialized pointer

CVSS Meta Temp Score
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CTI Interest Score
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3.0$0-$5k0.00+

Summaryinfo

A vulnerability categorized as problematic has been discovered in FFmpeg up to 9.0.2. This affects the function ff_jpegls_decode_picture of the file libavcodec/jpeglsdec.c of the component JPEG-LS Decoder. Executing a manipulation can lead to uninitialized pointer. This vulnerability is handled as CVE-2026-125243. It is possible to launch the attack on the local host. There is not any exploit available.

Detailsinfo

A vulnerability has been found in FFmpeg up to 9.0.2 and classified as problematic. This vulnerability affects the function ff_jpegls_decode_picture of the file libavcodec/jpeglsdec.c of the component JPEG-LS Decoder. The manipulation with an unknown input leads to a uninitialized pointer vulnerability. The CWE definition for the vulnerability is CWE-824. The product accesses or uses a pointer that has not been initialized. As an impact it is known to affect confidentiality. CVE summarizes:

FFmpeg through 9.0.2 contains an uninitialized memory disclosure vulnerability in ff_jpegls_decode_picture() in libavcodec/jpeglsdec.c, which decodes 16-bit line-interleaved JPEG-LS scans as 8-bit samples. Attackers can supply a crafted single-component JPEG-LS image with the ILV byte set to 1, causing decoded GRAY16 frames to expose leftover heap memory.

The advisory is shared for download at code.ffmpeg.org. This vulnerability was named CVE-2026-125243 since 11/09/2026. The exploitation appears 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.

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

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-2026-125243 (🔒)

GCVE (CVE): GCVE-0-2026-125243
GCVE (VulDB): GCVE-100-433336

Entryinfo

Created: 11/09/2026 20:48
Changes: 11/09/2026 20:48 (75)
Complete: 🔍
Cache ID: 216::103

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