SumatraPDF Heap Buffer Overflow DoS

The vulnerability of the MobiDoc::ParseHeader function in the src/MobiDoc.cpp file of the PDF, EPUB, MOBI, FB2, CHM, XPS, and DjVu viewing software SumatraPDF lies in the reading of data beyond the allowed range of memory. Exploiting this vulnerability can allow an attacker to cause a service...

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 MO...

CVE-2026-26054 SumatraPDF: Heap out-of-bounds read in MOBI header parser.

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 MO...

CVE-2026-26054 SumatraPDF: Heap out-of-bounds read in MOBI header parser.

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 MO...

CVE-2026-26054

SumatraPDF, a multi-format reader for Windows, is vulnerable to a heap out-of-bounds read in the MobiDoc::ParseHeader function within src/MobiDoc.cpp. The issue occurs because DecodeMobiDocHeader constructs a decoder sized for kMobiHeaderLen without verifying the actual remaining buffer length, e...

EUVD-2026-86296

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 MO...

CVE-2026-26054 SumatraPDF: Heap out-of-bounds read in MOBI header parser.

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 MO...

PT-2026-98141

Name of the Vulnerable Software and Affected Versions SumatraPDF versions prior to 3.6 Description The MobiDoc::ParseHeader function in src/MobiDoc.cpp validates records using kMobiHeaderMinLen, while DecodeMobiDocHeader creates a decoder sized for kMobiHeaderLen without verifying the actual...

CVE-2026-26054: Out-of-bounds Read

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 MO...