Log in Start free

Vulnerability · Published May 14, 2026 · Assigned by GitHub_M

CVE-2026-44673libyang: lyb_read_string() integer overflow → heap buffer overflow

High 7.5

In plain English

A high-severity integer overflow in libyang from CESNET. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 51% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)7.5High
Exploit odds (30 days)0.6%top 49.4% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known

Official 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.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
AlmaLinux:10libyang2.1.148-4.el10_2ALSA-2026:24758
AlmaLinux:8libyang1.0.184-2.el8_10ALSA-2026:24545
AlmaLinux:9libyang2.1.148-1.el9_8.1ALSA-2026:25051
AlmaLinux:10libyang-devel2.1.148-4.el10_2ALSA-2026:24758
AlmaLinux:9libyang-devel2.1.148-1.el9_8.1ALSA-2026:25051
AlmaLinux:10libyang-devel-doc2.1.148-4.el10_2ALSA-2026:24758
AlmaLinux:9libyang-devel-doc2.1.148-1.el9_8.1ALSA-2026:25051
Debian:13libyangno fix listedDEBIAN-CVE-2026-44673
Debian:14libyang6.4.13-1DEBIAN-CVE-2026-44673
Debian:12libyang2no fix listedDEBIAN-CVE-2026-44673
Rocky Linux:10libyang0:2.1.148-4.el10_2RLSA-2026:24758
Rocky Linux:8libyang0:1.0.184-2.el8_10RLSA-2026:24545
Rocky Linux:9libyang0:2.1.148-1.el9_8.1RLSA-2026:25051
Ubuntu:22.04:LTSlibyangno fix listedUBUNTU-CVE-2026-44673
Ubuntu:25.10libyangno fix listedUBUNTU-CVE-2026-44673
Ubuntu:26.04:LTSlibyangno fix listedUBUNTU-CVE-2026-44673
Ubuntu:22.04:LTSlibyang2no fix listedUBUNTU-CVE-2026-44673
Ubuntu:24.04:LTSlibyang2no fix listedUBUNTU-CVE-2026-44673

Affected products (as reported)

VendorProductVersions
CESNET libyang < SO 5.2.15

Weakness: CWE-190 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References