Out-of-bounds Read in Libtins
CVE-2026-112273
libtins through 4.6 contains a heap out-of-bounds read vulnerability in DNS::compose_name in src/dns.cpp that allows remote attackers to read past the packet buffer by sending a label ending exactly at the packet end. Attackers can deliver crafted DNS packets whose additional, answer, or authority records trigger a one-byte read when parsed, crashing applications on hardened allocators.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L.
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/@haindpwn/libtins-dns-name-parsing-oob-read (third-party-advisory)
- github.com/mfontanini/libtins/blob/v4.6/src/dns.cpp (technical-description)
- github.com/mfontanini/libtins (product)
- www.vulncheck.com/advisories/libtins-through-4.6-heap-out-of-bounds-read-via-dn… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-112273?
- CVE-2026-112273 is a medium-severity vulnerability in Libtins, classified under Out-of-bounds Read. CVSS score: 5.3/10. Published 2026-10-19.
- How severe is CVE-2026-112273?
- Medium severity. CVSS v3 base score is 5.3 out of 10.