FFmpeg – Out-of-Bounds Write in RASC Decoder decode_dlta()_CVE-2026-58049

{
    "lastseen": "",
    "description": "FFmpeg's RASC video decoder (decode_dlta in libavcodec/rasc.c) performs 32-bit reads and writes at the row cursor before the NEXT_LINE row-boundary check and validates the DLTA region in pixel rather than byte units, so a DLTA run on a PAL8 frame can access several bytes past the row allocation. A crafted media stream using the RASC FourCC, decoded by libavcodec, triggers a bitstream-controlled out-of-bounds heap write and adjacent out-of-bounds read, leading to memory corruption.",
    "published": "2026-06-28T01:32:52.900Z",
    "modified": "2026-06-28T01:32:52.900Z",
    "type": "cve",
    "title": "FFmpeg - Out-of-Bounds Write in RASC Decoder decode_dlta()",
    "source": "VulnCheck",
    "references": "https://github.com/bikini/exploitarium/tree/main/ffmpeg-rasc-dlta-calc-poc\nhttps://github.com/FFmpeg/FFmpeg/blob/master/libavcodec/rasc.c\nhttps://www.vulncheck.com/advisories/ffmpeg-out-of-bounds-write-in-rasc-decoder-decode-dlta",
    "id": "CVE-2026-58049",
    "bulletinFamily": "",
    "cwe": [
        "CWE-787"
    ],
    "cvelist": null,
    "sourceData": "FFmpeg FFmpeg 0",
    "sourceHref": "",
    "cvss": {
        "score": 8.6,
        "severity": "HIGH",
        "vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H",
        "version": "3.1"
    },
    "cvss2": [],
    "cvss3": {
        "version": "",
        "vectorString": "",
        "baseScore": 0,
        "baseSeverity": "",
        "attackVector": "",
        "attackComplexity": "",
        "privilegesRequired": "",
        "userInteraction": "",
        "scope": "",
        "confidentialityImpact": "",
        "integrityImpact": "",
        "availabilityImpact": "",
        "cvssV3": {
            "version": "",
            "vectorString": "",
            "baseScore": 0,
            "baseSeverity": "",
            "attackVector": "",
            "attackComplexity": "",
            "privilegesRequired": "",
            "userInteraction": "",
            "scope": "",
            "confidentialityImpact": "",
            "integrityImpact": "",
            "availabilityImpact": ""
        }
    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "FFmpeg",
    "version": "0",
    "vendor": "FFmpeg",
    "ai_description": "Out-of-bounds write in RASC decoder decode_dlta() function",
    "ai_severity": "High",
    "ai_vendor": "FFmpeg",
    "ai_product": "FFmpeg",
    "ai_version": "0",
    "ai_score": 8.6
}