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.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/mfontanini/libtins
https://github.com/mfontanini/libtins/blob/v4.6/src/dns.cpp#L338-L389
https://hackmd.io/@haindpwn/libtins-dns-name-parsing-oob-read
https://www.vulncheck.com/advisories/libtins-through-4.6-heap-out-of-bounds-read-via-dns-compose-name
https://hackmd.io/@haindpwn/cve-2026-112273-112274-libtins-dns-name-parsing-oob-read

Configurations

No configuration.

History

22 Oct 2026, 03:16

Type	Values Removed	Values Added
References		() https://hackmd.io/@haindpwn/cve-2026-112273-112274-libtins-dns-name-parsing-oob-read -

19 Oct 2026, 14:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-19 14:17

Updated : 2026-10-22 03:16

NVD link : CVE-2026-112273

Mitre link : CVE-2026-112273

CVE.ORG link : CVE-2026-112273

JSON object : View

Products Affected

No product.

CWE

CWE-125

Out-of-bounds Read

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