CVE-2026-23951 is an off-by-one error in SumatraPDF, a multi-format reader for Windows, affecting all versions. This vulnerability, triggered by a crafted Mobi file with exactly two records, leads to an integer underflow and an out-of-bounds heap read, causing the application to crash. With a CVSS score of 5.5 (Medium), it requires user interaction (UI:R) to open the malicious file, but has low attack complexity (AC:L) and no privileges required (PR:N), resulting in high availability impact (A:H). There are currently no published fixes, active exploits, or public exploit code available, though it has garnered some community discussion.
| Vendor | Product | Version(s) | CPE |
|---|---|---|---|
Range not provided by sourceCPE matchmatch criteria | cpe:2.3:a:sumatrapdfreader:sumatrapdf:-:*:*:*:*:*:*:* |
CVSS version used by this source: 3.1
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
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The average CVE in this peer group has 0.1 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.