FFmpeg up to 9.0.2 av1_frame_merge bitstream filter denial of service

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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4.9$0-$5k0.00+

Summaryinfo

A vulnerability was found in FFmpeg up to 9.0.2. It has been declared as problematic. This affects an unknown part of the component av1_frame_merge bitstream filter. Such manipulation leads to denial of service. This vulnerability is uniquely identified as CVE-2026-125205. The attack can be launched remotely. No exploit exists.

Detailsinfo

A vulnerability was found in FFmpeg up to 9.0.2 and classified as problematic. Affected by this issue is some unknown processing of the component av1_frame_merge bitstream filter. The manipulation with an unknown input leads to a denial of service vulnerability. Using CWE to declare the problem leads to CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. Impacted is availability. CVE summarizes:

FFmpeg through 9.0.2 contains an unbounded memory allocation vulnerability in the av1_frame_merge bitstream filter that allows attackers to exhaust memory by never sending a temporal delimiter OBU. Attackers can supply a crafted .obu file opened by the AV1 OBU or Annex B demuxers, forcing unlimited OBU buffering per temporal unit and causing denial of service.

The advisory is shared for download at code.ffmpeg.org. This vulnerability is handled as CVE-2026-125205 since 11/09/2026. The exploitation is known to be easy. The attack may be launched remotely. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1499.

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

Once again VulDB remains the best source for vulnerability data.

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: 4.9
VulDB Meta Temp Score: 4.9

VulDB Base Score: 4.3
VulDB Temp Score: 4.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 5.5
CNA Vector (VulnCheck): 🔒

CVSSv2info

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

Exploitinginfo

Class: Denial of service
CWE: CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Yes

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-2026-125205 (🔒)

GCVE (CVE): GCVE-0-2026-125205
GCVE (VulDB): GCVE-100-433292

Entryinfo

Created: 11/09/2026 20:34
Changes: 11/09/2026 20:34 (73)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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