FFmpeg up to 9.0.2 Tiertex SEQ Decoder libavcodec/tiertexseqv.c seq_decode_op1 stack-based overflow

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

Summaryinfo

A vulnerability, which was classified as problematic, was found in FFmpeg up to 9.0.2. Affected by this vulnerability is the function seq_decode_op1 of the file libavcodec/tiertexseqv.c of the component Tiertex SEQ Decoder. Executing a manipulation can lead to stack-based overflow. This vulnerability is handled as CVE-2026-125096. 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 seq_decode_op1 of the file libavcodec/tiertexseqv.c of the component Tiertex SEQ Decoder. The manipulation with an unknown input leads to a stack-based overflow vulnerability. The CWE definition for the vulnerability is CWE-121. The product writes past the end of a buffer that was allocated on the stack. As an impact it is known to affect confidentiality. CVE summarizes:

FFmpeg through 9.0.2 contains an uninitialized memory disclosure vulnerability in libavcodec/tiertexseqv.c that allows attackers to leak stack contents by triggering failed RLE unpacking. Attackers can supply a crafted Tiertex SEQ file so seq_decode_op1() copies an uninitialized 64-byte stack block into decoded frames, exposing stack memory in visible output.

The advisory is available at code.ffmpeg.org. This vulnerability was named CVE-2026-125096 since 11/09/2026. The exploitation appears 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

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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: Stack-based overflow
CWE: CWE-121 / 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-2026-125096 (🔒)

GCVE (CVE): GCVE-0-2026-125096
GCVE (VulDB): GCVE-100-433246

Entryinfo

Created: 11/09/2026 20:21
Changes: 11/09/2026 20:21 (75)
Complete: 🔍
Cache ID: 216::103

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