FFmpeg RIST Protocol Reader libavformat/librist.c librist_read heap-based overflow

CVSS Meta Temp Score
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CTI Interest Score
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8.4$0-$5k0.86

Summaryinfo

A vulnerability was found in FFmpeg. It has been declared as critical. The impacted element is the function librist_read of the file libavformat/librist.c of the component RIST Protocol Reader. Such manipulation leads to heap-based overflow. This vulnerability is traded as CVE-2026-75143. The attack may be launched remotely. There is no exploit available.

Detailsinfo

A vulnerability was found in FFmpeg (version now known) and classified as critical. Affected by this issue is the function librist_read of the file libavformat/librist.c of the component RIST Protocol Reader. The manipulation with an unknown input leads to a heap-based overflow vulnerability. Using CWE to declare the problem leads to 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(). Impacted is confidentiality, integrity, and availability. CVE summarizes:

FFmpeg before commit 1c10bcc contains a heap buffer overflow in the RIST protocol reader (libavformat/librist.c). librist_read() ignored its size argument and copied the full received payload length into the caller-provided destination buffer, overflowing it when the payload exceeds the destination size. This is reachable via the async:rist:// URL scheme, where the async wrapper supplies a smaller buffer than the received payload. A remote RIST sender can trigger the overflow by sending a packet whose payload exceeds the caller buffer size.

The advisory is shared for download at code.ffmpeg.org. This vulnerability is handled as CVE-2026-75143 since 08/17/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. There are known technical details, but no exploit is available.

Applying the patch 1c10bcc2e17255dacb717a25ab3db142ce390602 is able to eliminate this problem.

VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Type

Name

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: 8.5
VulDB Meta Temp Score: 8.4

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 9.8
CNA Vector (VulnCheck): 🔒

CVSSv2info

AVACAuCIA
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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: No
Local: No
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: 1c10bcc2e17255dacb717a25ab3db142ce390602

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-2026-75143 (🔒)
GCVE (CVE): GCVE-0-2026-75143
GCVE (VulDB): GCVE-100-393224

Entryinfo

Created: 08/19/2026 18:50
Changes: 08/19/2026 18:50 (76)
Complete: 🔍
Cache ID: 216::103

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