SumatraPDF is a multi-format reader for Windows. Prior to 3.6, the MobiDoc::ParseHeader function in src/MobiDoc.cpp validates a record using kMobiHeaderMinLen but DecodeMobiDocHeader constructs a decoder sized for kMobiHeaderLen without receiving the actual remaining buffer length. A malformed MOBI file can use an attacker-controlled header length to bypass optional-field early returns and cause the decoder to read beyond a short heap buffer. Opening the crafted document can crash SumatraPDF. This issue is fixed in version 3.6.

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History

Thu, 24 Sep 2026 19:15:00 +0000

Type Values Removed Values Added
First Time appeared Sumatrapdfreader
Sumatrapdfreader sumatrapdf
Vendors & Products Sumatrapdfreader
Sumatrapdfreader sumatrapdf

Thu, 24 Sep 2026 17:00:00 +0000

Type Values Removed Values Added
Description SumatraPDF is a multi-format reader for Windows. Prior to 3.6, the MobiDoc::ParseHeader function in src/MobiDoc.cpp validates a record using kMobiHeaderMinLen but DecodeMobiDocHeader constructs a decoder sized for kMobiHeaderLen without receiving the actual remaining buffer length. A malformed MOBI file can use an attacker-controlled header length to bypass optional-field early returns and cause the decoder to read beyond a short heap buffer. Opening the crafted document can crash SumatraPDF. This issue is fixed in version 3.6.
Title SumatraPDF: Heap out-of-bounds read in MOBI header parser.
Weaknesses CWE-125
References
Metrics cvssV4_0

{'score': 6.8, 'vector': 'CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N'}


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cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-09-24T16:48:03.247Z

Reserved: 2026-02-10T18:01:31.899Z

Link: CVE-2026-26054

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Deferred

Published: 2026-09-24T17:17:04.553

Modified: 2026-09-24T17:17:04.673

Link: CVE-2026-26054

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-09-24T19:00:15Z

Weaknesses