CVE-2026-44673

HIGH

libyang: lyb_read_string() integer overflow → heap buffer overflow

Title source: cna
STIX 2.1

Description

libyang is a YANG data modeling language library. Prior to SO 5.2.15, lyb_read_string() in src/parser_lyb.c contains an integer overflow that results in a heap buffer overflow when parsing a maliciously crafted LYB binary blob. An attacker who can supply LYB data to any libyang consumer (NETCONF server, sysrepo, etc.) can trigger a crash or potential heap corruption. This vulnerability is fixed in SO 5.2.15.

References (1)

Core 1
Core References

Scores

CVSS v3 7.5
EPSS 0.0027
EPSS Percentile 18.8%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CISA SSVC

Vulnrichment
Exploitation poc
Automatable yes
Technical Impact partial

Details

CWE
CWE-190
Status published
Products (1)
CESNET/libyang < SO 5.2.15
Published May 14, 2026
Tracked Since May 15, 2026