FFmpeg up to 9.0.2 APNG encoder libavcodec/pngenc.c encode_apng heap-based overflow

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 has been found in FFmpeg up to 9.0.2. Affected by this issue is the function encode_apng of the file libavcodec/pngenc.c of the component APNG encoder. The manipulation leads to heap-based overflow. This vulnerability is listed as CVE-2026-125218. The attack must be carried out locally. There is no available exploit.

Detailsinfo

A vulnerability was found in FFmpeg up to 9.0.2. It has been rated as problematic. This issue affects the function encode_apng of the file libavcodec/pngenc.c of the component APNG encoder. The manipulation with an unknown input leads to a heap-based overflow vulnerability. Using CWE to declare the problem leads to CWE-122. The product writes past the end of a buffer that was allocated on the heap. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

FFmpeg through 9.0.2 contains a heap buffer overflow vulnerability in the APNG encoder's encode_apng() function in libavcodec/pngenc.c when frame size changes mid-stream. Attackers can supply crafted media whose resolution grows mid-stream, causing APNG_DISPOSE_OP_BACKGROUND memset writes past prev_frame and crashing or corrupting heap memory in transcoding applications.

The advisory is shared at code.ffmpeg.org. The identification of this vulnerability is CVE-2026-125218 since 11/09/2026. The exploitation is known to be easy. An attack has to be approached locally. It demands that the victim is doing some kind of user interaction. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (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.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

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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: Heap-based overflow
CWE: CWE-122 / 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-2026-125218 (🔒)

GCVE (CVE): GCVE-0-2026-125218
GCVE (VulDB): GCVE-100-433313

Entryinfo

Created: 11/09/2026 20:41
Changes: 11/09/2026 20:41 (75)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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