CVE-2026-125218
Full vulnerability record from the local CVENow database.
Description
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.
Severity
HIGH
CVSS score
7.3
(v4.0)
Vulnerability status
Received
Source identifier
Published
2026-11-09 19:16:59.043000
Last modified
2026-11-09 19:16:59.043000
View original CVE JSON
{
"id": "CVE-2026-125218",
"sourceIdentifier": "[email protected]",
"published": "2026-11-09T19:16:59.043",
"lastModified": "2026-11-09T19:16:59.043",
"vulnStatus": "Received",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "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."
}
],
"affected": [
{
"source": "[email protected]",
"affectedData": [
{
"vendor": "FFmpeg",
"product": "FFmpeg",
"defaultStatus": "unaffected",
"repo": "https://code.ffmpeg.org/FFmpeg/FFmpeg",
"packageURL": "pkg:github/ffmpeg/ffmpeg",
"versions": [
{
"version": "0",
"lessThanOrEqual": "9.0.2",
"versionType": "semver",
"status": "affected"
}
]
}
]
}
],
"metrics": {
"cvssMetricV40": [
{
"source": "[email protected]",
"type": "Secondary",
"cvssData": {
"version": "4.0",
"vectorString": "CVSS:4.0/AV:L/AC:H/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
"baseScore": 7.3,
"baseSeverity": "HIGH",
"attackVector": "LOCAL",
"attackComplexity": "HIGH",
"attackRequirements": "PRESENT",
"privilegesRequired": "NONE",
"userInteraction": "PASSIVE",
"vulnConfidentialityImpact": "HIGH",
"vulnIntegrityImpact": "HIGH",
"vulnAvailabilityImpact": "HIGH",
"subConfidentialityImpact": "NONE",
"subIntegrityImpact": "NONE",
"subAvailabilityImpact": "NONE",
"exploitMaturity": "NOT_DEFINED",
"confidentialityRequirement": "NOT_DEFINED",
"integrityRequirement": "NOT_DEFINED",
"availabilityRequirement": "NOT_DEFINED",
"modifiedAttackVector": "NOT_DEFINED",
"modifiedAttackComplexity": "NOT_DEFINED",
"modifiedAttackRequirements": "NOT_DEFINED",
"modifiedPrivilegesRequired": "NOT_DEFINED",
"modifiedUserInteraction": "NOT_DEFINED",
"modifiedVulnConfidentialityImpact": "NOT_DEFINED",
"modifiedVulnIntegrityImpact": "NOT_DEFINED",
"modifiedVulnAvailabilityImpact": "NOT_DEFINED",
"modifiedSubConfidentialityImpact": "NOT_DEFINED",
"modifiedSubIntegrityImpact": "NOT_DEFINED",
"modifiedSubAvailabilityImpact": "NOT_DEFINED",
"Safety": "NOT_DEFINED",
"Automatable": "NOT_DEFINED",
"Recovery": "NOT_DEFINED",
"valueDensity": "NOT_DEFINED",
"vulnerabilityResponseEffort": "NOT_DEFINED",
"providerUrgency": "NOT_DEFINED"
}
}
],
"cvssMetricV31": [
{
"source": "[email protected]",
"type": "Primary",
"cvssData": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H",
"baseScore": 7.0,
"baseSeverity": "HIGH",
"attackVector": "LOCAL",
"attackComplexity": "HIGH",
"privilegesRequired": "NONE",
"userInteraction": "REQUIRED",
"scope": "UNCHANGED",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"availabilityImpact": "HIGH"
},
"exploitabilityScore": 1.0,
"impactScore": 5.9
}
]
},
"weaknesses": [
{
"source": "[email protected]",
"type": "Primary",
"description": [
{
"lang": "en",
"value": "CWE-122"
}
]
}
],
"references": [
{
"url": "https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/25682",
"source": "[email protected]"
},
{
"url": "https://github.com/FFmpeg/FFmpeg",
"source": "[email protected]"
},
{
"url": "https://github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/pngenc.c#L1148",
"source": "[email protected]"
},
{
"url": "https://github.com/FFmpeg/FFmpeg/commit/9b99973b2bbecee0b7e1e57035b95498b42f54a6",
"source": "[email protected]"
},
{
"url": "https://www.vulncheck.com/advisories/ffmpeg-through-9.0.2-apng-encoder-heap-buffer-overflow-via-encode-apng",
"source": "[email protected]"
}
]
}