Integer overflow in Chmlib
CVE-2025-48172
CHMLib through 2bef8d0, as used in SumatraPDF and other products, has a chm_lib.c _chm_decompress_block integer overflow. There is a resultant heap-based buffer overflow in _chm_fetch_bytes.
Vulnerability class: Integer Overflow
EPSS: 0.002 (5.0th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 5.6 (Medium). Vector: CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:L.
Affected products
- Chmlib — versions 0
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2025-48172?
- CVE-2025-48172 is a medium-severity vulnerability in Chmlib, classified under Integer Overflow or Wraparound. CVSS score: 5.6/10. Published 2025-07-04.
- How severe is CVE-2025-48172?
- Medium severity. CVSS v3 base score is 5.6 out of 10.