CVE-2020-36430

libass 0.15.x before 0.15.1 has a heap-based buffer overflow in decodechars (called from decodefont and process_text) because the wrong integer data type is used for subtraction.

Database specific

{
    "unresolved_ranges": [
        {
            "cpes": [
                "cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*"
            ],
            "source": "CPE_STRING",
            "extracted_events": [
                {
                    "introduced": "34"
                },
                {
                    "last_affected": "34"
                }
            ],
            "vendor_product": "fedoraproject:fedora"
        }
    ]
}

References

Affected packages

Git / github.com/libass/libass

Affected ranges

Type

GIT

Repo

https://github.com/libass/libass

Events

Introduced

d149636f502f5774ae1a8fb4c554b122674393b2

Fixed

5447214643eacef71776350e779adf4b6c07bb3b

Fixed

017137471d0043e0321e377ed8da48e45a3ec632

Database specific

{
    "cpe": "cpe:2.3:a:libass_project:libass:*:*:*:*:*:*:*:*",
    "source": [
        "CPE_RANGE",
        "REFERENCES"
    ],
    "extracted_events": [
        {
            "introduced": "0.15.0"
        },
        {
            "fixed": "0.15.1"
        }
    ]
}

Affected versions

0.*

0.15.0

Database specific

vanir_signatures_modified

"2026-07-08T17:56:24Z"

vanir_signatures

[
    {
        "signature_type": "Function",
        "target": {
            "file": "libass/ass.c",
            "function": "decode_font"
        },
        "deprecated": false,
        "source": "https://github.com/libass/libass/commit/017137471d0043e0321e377ed8da48e45a3ec632",
        "id": "CVE-2020-36430-1e115502",
        "signature_version": "v1",
        "digest": {
            "function_hash": "110991188393091881186985668039830991525",
            "length": 1124.0
        }
    },
    {
        "signature_type": "Line",
        "target": {
            "file": "libass/ass.c"
        },
        "deprecated": false,
        "source": "https://github.com/libass/libass/commit/017137471d0043e0321e377ed8da48e45a3ec632",
        "id": "CVE-2020-36430-dd9ed4a7",
        "signature_version": "v1",
        "digest": {
            "line_hashes": [
                "237761427446648667051004743683370618705",
                "203614521959843642792803634604266039747",
                "167057952582482068803313308181837134398",
                "185673660414575620126904484215688046936",
                "78573754609072835798149174981656735930",
                "103499063678342063401077868684384475532",
                "334814143342617232491248731862329862754",
                "124461199810427598757175082018620638494"
            ],
            "threshold": 0.9
        }
    }
]

source

"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2020-36430.json"