--- id: CVE-2026-44673 title: libyang is a YANG data modeling language library summary: >- 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 attack… severity: high cvss: 7.5 cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H' cwe: - CWE-190 vendor: CESNET product: libyang affected: - libyang < SO 5.2.15 patched: - enterprise_linux_appstream_eus_v_10_0 - enterprise_linux_appstream_v_10 - enterprise_linux_appstream_v_8 - enterprise_linux_appstream_aus_v_8_4 - enterprise_linux_appstream_eus_extension_v_8_4 - enterprise_linux_appstream_aus_v_8_6 - enterprise_linux_appstream_eus_extension_v_8_6 - enterprise_linux_appstream_e4s_v_8_8 - enterprise_linux_appstream_tus_v_8_8 - enterprise_linux_appstream_e4s_v_9_4 - enterprise_linux_appstream_v_9 - enterprise_linux_codeready_linux_builder_v_10 - enterprise_linux_codeready_linux_builder_v_9 published: '2026-05-14' updated: '2026-09-09' sourceUpdated: '2026-09-09T13:20:11.590' source: NVD sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-44673' references: - url: 'https://github.com/CESNET/libyang/security/advisories/GHSA-vw2p-pq79-92xh' label: security-advisories@github.com - url: 'https://access.redhat.com/errata/RHSA-2026:24545' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://access.redhat.com/errata/RHSA-2026:24758' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://access.redhat.com/errata/RHSA-2026:25051' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://access.redhat.com/errata/RHSA-2026:49666' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://access.redhat.com/errata/RHSA-2026:51339' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://access.redhat.com/errata/RHSA-2026:51351' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://access.redhat.com/errata/RHSA-2026:51368' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://access.redhat.com/errata/RHSA-2026:65467' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://access.redhat.com/errata/RHSA-2026:65477' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://access.redhat.com/errata/RHSA-2026:65508' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://access.redhat.com/security/cve/CVE-2026-44673' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2477617' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://github.com/CESNET/libyang/security/advisories/GHSA-vw2p-pq79-92xh' label: 134c704f-9b21-4f2e-91b3-4a467353bcc0 - url: >- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-44673.json label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://www.cve.org/CVERecord?id=CVE-2026-44673' - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-44673' tags: - nvd - cve.org - exploit-available - csaf - vex - red-hat exploitAvailable: true ssvc: exploitation: poc automatable: 'yes' technicalImpact: partial timestamp: '2026-05-15T14:18:31.145491Z' epss: 0.00953 epssPercentile: 0.59666 ingestedAt: '2026-08-07T13:14:10.235Z' --- ## Overview 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. ## Remediation Refer to the linked advisories for vendor-supplied fixes and affected version ranges. ## Vendor advisories - **RHSA-2026:49666** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream EUS (v. 10.0) · released 2026-08-03 · [advisory](https://access.redhat.com/errata/RHSA-2026:49666) - **RHSA-2026:24758** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 10), Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) · released 2026-06-09 · [advisory](https://access.redhat.com/errata/RHSA-2026:24758) - **RHSA-2026:24545** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 8) · released 2026-06-08 · [advisory](https://access.redhat.com/errata/RHSA-2026:24545) - **RHSA-2026:51351** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream AUS (v.8.4), Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) · released 2026-08-06 · [advisory](https://access.redhat.com/errata/RHSA-2026:51351) - **RHSA-2026:51368** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream AUS (v.8.6), Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) · released 2026-08-06 · [advisory](https://access.redhat.com/errata/RHSA-2026:51368) - **RHSA-2026:51339** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream E4S (v.8.8), Red Hat Enterprise Linux AppStream TUS (v.8.8) · released 2026-08-06 · [advisory](https://access.redhat.com/errata/RHSA-2026:51339) - **RHSA-2026:65467** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream E4S (v.9.4) · released 2026-09-08 · [advisory](https://access.redhat.com/errata/RHSA-2026:65467) - **RHSA-2026:25051** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 9), Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) · released 2026-06-10 · [advisory](https://access.redhat.com/errata/RHSA-2026:25051) - **RHSA-2026:65508** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream EUS (v.9.6) · released 2026-09-08 · [advisory](https://access.redhat.com/errata/RHSA-2026:65508) - **RHSA-2026:65477** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream E4S (v.9.2) · released 2026-09-08 · [advisory](https://access.redhat.com/errata/RHSA-2026:65477)