sumatrapdfreader SumatraPDF up to 3.5.2 on Windows MOBI HuffDic Decompressor AddCdicData out-of-bounds

CVSS Meta Temp Score
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CTI Interest Score
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4.8$0-$5k0.00

Summaryinfo

A vulnerability classified as problematic has been found in sumatrapdfreader SumatraPDF up to 3.5.2 on Windows. Affected by this issue is the function AddCdicData of the component MOBI HuffDic Decompressor. The manipulation leads to out-of-bounds. This vulnerability is documented as CVE-2026-25920. The attack can be initiated remotely. There is not any exploit available. It is recommended to apply a patch to fix this issue.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in sumatrapdfreader SumatraPDF up to 3.5.2 on Windows. This issue affects the function AddCdicData of the component MOBI HuffDic Decompressor. The manipulation with an unknown input leads to a out-of-bounds vulnerability. Using CWE to declare the problem leads to CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. Impacted is availability. The summary by CVE is:

SumatraPDF is a multi-format reader for Windows. In 3.5.2 and earlier, a heap out-of-bounds read vulnerability exists in SumatraPDF's MOBI HuffDic decompressor. The bounds check in AddCdicData() only validates half the range that DecodeOne() actually accesses. Opening a crafted .mobi file can read nearly (1 << codeLength) bytes beyond the CDIC dictionary buffer, leading to a crash.

It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2026-25920 since 02/09/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. It demands that the victim is doing some kind of user interaction. Technical details of the vulnerability are known, but there is no available exploit.

Applying the patch 12b6887e9dfff874fe8749bab1bdc53d4ff075b3 is able to eliminate this problem. The bugfix is ready for download at github.com.

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Productinfo

Vendor

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Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.9
VulDB Meta Temp Score: 4.8

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 5.5
CNA Vector (GitHub_M): 🔒

CVSSv2info

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Out-of-bounds
CWE: CWE-125 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔒

Patch: 12b6887e9dfff874fe8749bab1bdc53d4ff075b3

Timelineinfo

02/09/2026 CVE reserved
02/10/2026 +1 days Advisory disclosed
02/10/2026 +0 days VulDB entry created
02/21/2026 +11 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-5mwx-65x7-cffp
Status: Confirmed

CVE: CVE-2026-25920 (🔒)
GCVE (CVE): GCVE-0-2026-25920
GCVE (VulDB): GCVE-100-345071

Entryinfo

Created: 02/10/2026 03:20
Updated: 02/21/2026 10:00
Changes: 02/10/2026 03:20 (68), 02/12/2026 11:08 (1), 02/21/2026 10:00 (1)
Complete: 🔍
Cache ID: 216::103

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