FFmpeg up to 9.0.2 CBS SEI libavcodec/cbs_sei.c cbs_sei_delete_message double free

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.9$0-$5k0.00+

Summaryinfo

A vulnerability classified as problematic was found in FFmpeg up to 9.0.2. Impacted is the function cbs_sei_delete_message of the file libavcodec/cbs_sei.c of the component CBS SEI. Such manipulation leads to double free. This vulnerability is listed as CVE-2026-125269. The attack must be carried out locally. There is no available exploit.

Detailsinfo

A vulnerability was found in FFmpeg up to 9.0.2 and classified as problematic. Affected by this issue is the function cbs_sei_delete_message of the file libavcodec/cbs_sei.c of the component CBS SEI. The manipulation with an unknown input leads to a double free vulnerability. Using CWE to declare the problem leads to CWE-415. The product calls free() twice on the same memory address. Impacted is confidentiality, integrity, and availability. CVE summarizes:

FFmpeg through 9.0.2 contains a double free vulnerability in libavcodec/cbs_sei.c where cbs_sei_delete_message() leaves a stale extension_data reference that ff_cbs_sei_add_message() reuses. Attackers can supply a crafted H.264 stream with a display orientation SEI message followed by payload extension data, processed by h264_metadata with display_orientation=insert, to corrupt heap memory.

The advisory is shared for download at code.ffmpeg.org. This vulnerability is handled as CVE-2026-125269 since 11/09/2026. The exploitation is known 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

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: 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

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

Exploitinginfo

Class: Double free
CWE: CWE-415 / CWE-119
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-2026-125269 (🔒)

GCVE (CVE): GCVE-0-2026-125269
GCVE (VulDB): GCVE-100-433328

Entryinfo

Created: 11/09/2026 20:45
Changes: 11/09/2026 20:45 (75)
Complete: 🔍
Cache ID: 216::103

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