High severity · published May 14, 2026
CVE-2026-44673
libyang: lyb_read_string() integer overflow → heap buffer overflow
7.5
CVSS
0.6%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 50% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
libyang · CESNET
< SO 5.2.15 · source: vendor
RH
Red Hat Enterprise Linux 10 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Enterprise Linux 10.0 Extended Update Support · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Enterprise Linux 8 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Enterprise Linux 8.8 Telecommunications Update Service · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Enterprise Linux 9 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions · Red Hat
All versions, or not specified · source: CISA
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-44673
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-44673
github.com
https://github.com/CESNET/libyang/security/advisories/GHSA-vw2p-pq79-92xh
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:24545
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:24758
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:25051
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:49666
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:51339
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