CVE-2026-70630

FFmpeg versions from 3.0 up to, but not including, 9.0 contain an uninitialized heap memory read vulnerability in the native Screenpresso decoder (libavcodec/screenpresso.c) that allows attackers to recover sensitive memory contents by supplying a crafted SPV1 packet with a valid zlib stream that decompresses fewer bytes than the full frame requires. The screenpresso_decode_frame() function fails to validate the produced byte count before calling av_image_copy_plane() to copy the complete frame dimensions from the persistent ctx->inflated_buf buffer, causing unwritten heap memory from prior allocations or prior frames to be copied into decoded output and potentially exposing sensitive data such as userspace addresses from persistent decoding services.

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/705890061467ad550ecc1dad5eea07f28ccfb43e	Patch
https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/9a3202a98b2e095b54dd784c3e01a09a676fc3fa	Patch
https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/c22667d0fd7916a33fd3e79685b7246fc48f1a62	Patch
https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/23896	Issue Tracking Patch
https://www.vulncheck.com/advisories/ffmpeg-uninitialized-heap-memory-read-in-screenpresso-decoder	Patch Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:ffmpeg:ffmpeg:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-08-06 22:18

Updated : 2026-09-01 15:35

NVD link : CVE-2026-70630

Mitre link : CVE-2026-70630

CVE.ORG link : CVE-2026-70630

JSON object : View

Products Affected

ffmpeg

ffmpeg

CWE

CWE-908

Use of Uninitialized Resource

{"id": "CVE-2026-70630", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-70630", "role": "CISA Coordinator", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "version": "2.0.3", "timestamp": "2026-08-07T17:09:51.127288Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "disclosure@vulncheck.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.5, "attackVector": "LOCAL", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N", "integrityImpact": "NONE", "userInteraction": "REQUIRED", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}, "impactScore": 3.6, "exploitabilityScore": 1.8}], "cvssMetricV40": [{"type": "Secondary", "source": "disclosure@vulncheck.com", "cvssData": {"Safety": "NOT_DEFINED", "version": "4.0", "Recovery": "NOT_DEFINED", "baseScore": 6.8, "Automatable": "NOT_DEFINED", "attackVector": "LOCAL", "baseSeverity": "MEDIUM", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:N/VA:N/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", "exploitMaturity": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "userInteraction": "PASSIVE", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "subIntegrityImpact": "NONE", "vulnIntegrityImpact": "NONE", "integrityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "availabilityRequirement": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "subConfidentialityImpact": "NONE", "vulnConfidentialityImpact": "HIGH", "confidentialityRequirement": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED"}}]}, "affected": [{"source": "disclosure@vulncheck.com", "affectedData": [{"repo": "https://code.ffmpeg.org/FFmpeg/FFmpeg", "vendor": "FFmpeg", "product": "FFmpeg", "versions": [{"status": "affected", "version": "3.0", "lessThan": "9.0", "versionType": "custom"}], "packageURL": "pkg:github/FFmpeg/FFmpeg", "defaultStatus": "unaffected"}]}], "published": "2026-08-06T22:18:27.273", "references": [{"url": "https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/705890061467ad550ecc1dad5eea07f28ccfb43e", "tags": ["Patch"], "source": "disclosure@vulncheck.com"}, {"url": "https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/9a3202a98b2e095b54dd784c3e01a09a676fc3fa", "tags": ["Patch"], "source": "disclosure@vulncheck.com"}, {"url": "https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/c22667d0fd7916a33fd3e79685b7246fc48f1a62", "tags": ["Patch"], "source": "disclosure@vulncheck.com"}, {"url": "https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/23896", "tags": ["Issue Tracking", "Patch"], "source": "disclosure@vulncheck.com"}, {"url": "https://www.vulncheck.com/advisories/ffmpeg-uninitialized-heap-memory-read-in-screenpresso-decoder", "tags": ["Patch", "Third Party Advisory"], "source": "disclosure@vulncheck.com"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Secondary", "source": "disclosure@vulncheck.com", "description": [{"lang": "en", "value": "CWE-908"}]}], "descriptions": [{"lang": "en", "value": "FFmpeg versions from 3.0 up to, but not including, 9.0 contain an uninitialized heap memory read vulnerability in the native Screenpresso decoder (libavcodec/screenpresso.c) that allows attackers to recover sensitive memory contents by supplying a crafted SPV1 packet with a valid zlib stream that decompresses fewer bytes than the full frame requires. The screenpresso_decode_frame() function fails to validate the produced byte count before calling av_image_copy_plane() to copy the complete frame dimensions from the persistent ctx->inflated_buf buffer, causing unwritten heap memory from prior allocations or prior frames to be copied into decoded output and potentially exposing sensitive data such as userspace addresses from persistent decoding services."}], "lastModified": "2026-09-01T15:35:24.127", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:ffmpeg:ffmpeg:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "A5AA28CB-44E7-444C-864D-68E06140801E", "versionEndExcluding": "9", "versionStartIncluding": "3.0"}], "operator": "OR"}]}], "sourceIdentifier": "disclosure@vulncheck.com"}