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

2026-10-28T11:06:07Z

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":  [
                {
                    "range":  [
                        {
                            "last_affected":  "3.7.0.22298"
                        }
                    ],
                    "source":  "AFFECTED_FIELD",
                    "strategy":  "StringRangeExpression"
                }
            ]
        }
    ]
}

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

{
    "extracted_events":  [
        {
            "range":  [
                {
                    "fixed":  "1ef900cbad02f06353b0a0747b098ca596f7c131"
                }
            ],
            "source":  "REFERENCES_COMMIT"
        }
    ]
}

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

"2026-10-28T11:06:07Z"