CVE-2026-107729

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Source

https://cve.org/CVERecord?id=CVE-2026-107729

Import Source

https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-107729.json

JSON Data

https://api.osv.dev/v1/vulns/CVE-2026-107729

Aliases

GHSA-86hq-m6hv-67h2

Published

2026-10-08T22:18:40Z

Modified

2026-10-10T07:05:58Z

Severity

5.5 (Medium) CVSS_V3 - CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H CVSS Calculator

Summary

SumatraPDF: Unsigned-to-signed hdrLen validation bypass in SumatraPDF MOBI parsing causes out-of-bounds read

Details

SumatraPDF is a multi-format reader for Windows. In 3.7.0.22298, src/MobiDoc.cpp narrows the untrusted unsigned mobiHdr.hdrLen field to a signed integer for validation; values above INT_MAX become negative and bypass the upper-bound check. When the EXTH flag is set, the original unsigned value is reused as a pointer offset, causing DecodeExthHeader() to read beyond the record buffer. Opening a crafted MOBI file can reliably terminate the application with a native access violation; no code execution, information disclosure, or integrity impact has been demonstrated. No fixed version is available as of this review.

Database specific

{
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
        "CWE-125"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/107xxx/CVE-2026-107729.json",
    "unresolved_ranges": [
        {
            "extracted_events": [
                {
                    "last_affected": "3.7.0.22298"
                }
            ],
            "source": "AFFECTED_FIELD"
        }
    ]
}

References

Affected packages

Git / github.com/sumatrapdfreader/sumatrapdf

Affected ranges

Type

GIT

Repo

https://github.com/sumatrapdfreader/sumatrapdf

Events

Introduced

Fixed

1ef900cbad02f06353b0a0747b098ca596f7c131

Database specific

Show details

{
    "source": "REFERENCES"
}

Affected versions

1.*

1.4split

1.5split

1.6split

1.7split

1.8split

1.9split

2.*

2.0split

2.1split

2.2split

2.3split

2.4split

2.5split

3.*

3.0split

3.1.2rel

3.2

Database specific

source

"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-107729.json"

vanir_signatures

[
    {
        "deprecated": false,
        "digest": {
            "function_hash": "93172328152261526065464032138813401950",
            "length": 3668
        },
        "id": "CVE-2026-107729-3120276e",
        "signature_type": "Function",
        "signature_version": "v1",
        "source": "https://github.com/sumatrapdfreader/sumatrapdf/commit/1ef900cbad02f06353b0a0747b098ca596f7c131",
        "target": {
            "file": "src/MobiDoc.cpp",
            "function": "MobiDoc::ParseHeader"
        }
    },
    {
        "deprecated": false,
        "digest": {
            "line_hashes": [
                "1541939507829464741408512456049284756",
                "189737415210981728699583238804399781442",
                "55212916160740621400692300896212763609",
                "95428735127564320031064104690942797273"
            ],
            "threshold": 0.9
        },
        "id": "CVE-2026-107729-7f059528",
        "signature_type": "Line",
        "signature_version": "v1",
        "source": "https://github.com/sumatrapdfreader/sumatrapdf/commit/1ef900cbad02f06353b0a0747b098ca596f7c131",
        "target": {
            "file": "src/MobiDoc.cpp"
        }
    }
]

vanir_signatures_modified

"2026-10-10T07:05:58Z"