FFmpeg hvcC box writer heap-based overflow

CVSS Meta Temp Score
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CTI Interest Score
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6.9$0-$5k0.89-

Summaryinfo

A vulnerability was found in FFmpeg. It has been classified as critical. The affected element is an unknown function of the component hvcC box writer. This manipulation causes heap-based overflow. This vulnerability appears as CVE-2026-75141. The attack may be initiated remotely. There is no available exploit.

Detailsinfo

A vulnerability has been found in FFmpeg (unknown version) and classified as critical. Affected by this vulnerability is an unknown code block of the component hvcC box writer. The manipulation with an unknown input leads to a heap-based overflow vulnerability. The CWE definition for the vulnerability is CWE-122. A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc(). As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

FFmpeg before commit acf5d7c contains a heap buffer overflow in the hvcC box writer. When writing an HEVC configuration record with more NAL units of a single type than the count field can represent, the NAL unit count overflows, causing a heap buffer overflow. A crafted HEVC input file triggers the overflow during muxing.

It is possible to read the advisory at code.ffmpeg.org. This vulnerability is known as CVE-2026-75141 since 08/17/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. It demands that the victim is doing some kind of user interaction. The technical details are unknown and an exploit is not publicly available.

Applying the patch acf5d7cdc1f9ae8752c23e1ea8d7f355ed780781 is able to eliminate this problem.

Be aware that VulDB is the high quality source for vulnerability data.

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: 7.0
VulDB Meta Temp Score: 6.9

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.8
CNA Vector (VulnCheck): 🔒

CVSSv2info

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

Exploitinginfo

Class: Heap-based overflow
CWE: CWE-122 / CWE-119
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: Patch
Status: 🔍

0-Day Time: 🔒

Patch: acf5d7cdc1f9ae8752c23e1ea8d7f355ed780781

Timelineinfo

08/17/2026 CVE reserved
08/19/2026 +2 days Advisory disclosed
08/19/2026 +0 days VulDB entry created
08/19/2026 +0 days VulDB entry last update

Sourcesinfo

Product: ffmpeg.org

Advisory: code.ffmpeg.org
Status: Confirmed

CVE: CVE-2026-75141 (🔒)
GCVE (CVE): GCVE-0-2026-75141
GCVE (VulDB): GCVE-100-393223

Entryinfo

Created: 08/19/2026 18:49
Changes: 08/19/2026 18:49 (74)
Complete: 🔍
Cache ID: 216::103

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