Out-of-bounds Read in Sumatrapdfreader Sumatrapdf
CVE-2026-25920
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…
Vulnerability class: Buffer Overflow
EPSS: 0.002 (12.1th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H.
Affected products
- Sumatrapdfreader Sumatrapdf — versions <= 3.5.2
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Exploit, Vendor Advisory)
- security-advisories@github.com (Product, x_refsource_MISC)
- security-advisories@github.com (Product, x_refsource_MISC)
Frequently asked questions
- What is CVE-2026-25920?
- CVE-2026-25920 is a medium-severity vulnerability in Sumatrapdfreader Sumatrapdf, classified under Out-of-bounds Read. CVSS score: 5.5/10. Published 2026-02-09.
- How severe is CVE-2026-25920?
- Medium severity. CVSS v3 base score is 5.5 out of 10.