Out-of-bounds Read in Sumatrapdfreader Sumatrapdf
CVE-2026-26054
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.
Vulnerability class: Buffer Overflow
Published · last modified .
EPSS exploit prediction
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Affected products
- Sumatrapdfreader Sumatrapdf — versions < 3.6