Out-of-bounds Read in Konstanty Bialkowski Libmodplug
CVE-2026-111271
libmodplug through 0.8.9.1 contains a heap-based out-of-bounds read vulnerability in CSoundFile::ReadAMS2() in src/load_ams.cpp that allows attackers to read adjacent heap memory via crafted AMS files. Attackers can supply an AMS module whose pattern effect bytes keep bit 7 set, driving the decoder past the input buffer and crashing any libmodplug consumer.
Vulnerability class: Buffer Overflow
Published · last modified .
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.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- hackmd.io/@haind-pwn/libmodplug-dsm-pattern-oob-write (technical-description)
- github.com/Konstanty/libmodplug/blob/d1b97ed0020bc620a059d3675d1854b40bd2608d/s… (technical-description)
- github.com/Konstanty/libmodplug (product)
- www.vulncheck.com/advisories/libmodplug-through-0.8.9.1-heap-out-of-bounds-read… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-111271?
- CVE-2026-111271 is a medium-severity vulnerability in Konstanty Bialkowski Libmodplug, classified under Out-of-bounds Read. CVSS score: 5.5/10. Published 2026-10-15.
- How severe is CVE-2026-111271?
- Medium severity. CVSS v3 base score is 5.5 out of 10.