Vulnerability-Lookup

rlsa-2026:25051

Vulnerability from osv_rocky

Published

2026-06-13 00:03

Modified

2026-06-27 00:06

Summary

Important: libyang security update

Details

Libyang is YANG data modeling language parser and toolkit written (and providing API) in C.

Security Fix(es):

libyang: libyang: Denial of Service or arbitrary code execution via maliciously crafted LYB binary blob (CVE-2026-44673)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Severity

7.5 (High)


                    
                      CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Credits

Rocky Enterprise Software Foundation

Red Hat

References

URL

Type

	https://errata.rockylinux.org/RLSA-2026:25051	ADVISORY
	https://bugzilla.redhat.com/show_bug.cgi?id=2477617	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "Rocky Linux:9",
        "name": "libyang",
        "purl": "pkg:rpm/rocky-linux/libyang?distro=rocky-linux-9\u0026epoch=0"
      },
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            },
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              "fixed": "0:2.1.148-1.el9_8.1"
            }
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          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "credits": [
    {
      "name": "Rocky Enterprise Software Foundation"
    },
    {
      "name": "Red Hat"
    }
  ],
  "details": "Libyang is YANG data modeling language parser and toolkit written (and providing API) in C.\n\nSecurity Fix(es):\n\n* libyang: libyang: Denial of Service or arbitrary code execution via maliciously crafted LYB binary blob (CVE-2026-44673)\n\nFor more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.",
  "id": "RLSA-2026:25051",
  "modified": "2026-06-27T00:06:15.904632Z",
  "published": "2026-06-13T00:03:17.085789Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://errata.rockylinux.org/RLSA-2026:25051"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2477617"
    }
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Important: libyang security update",
  "upstream": [
    "CVE-2026-44673"
  ]
}

CVE-2026-44673 (GCVE-0-2026-44673)

Vulnerability from cvelistv5 – Published: 2026-05-14 20:35 – Updated: 2026-07-15 00:53

Title

libyang: lyb_read_string() integer overflow → heap buffer overflow

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 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.

Severity

7.5 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

SSVC

Exploitation: poc Automatable: yes Technical Impact: partial

CISA Coordinator (v2.0.3)

CWE

CWE-190 - Integer Overflow or Wraparound

Assigner

GitHub_M

References

7 references

URL	Tags
https://github.com/CESNET/libyang/security/adviso…	x_refsource_CONFIRM
https://access.redhat.com/security/cve/CVE-2026-44673	vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2477617	issue-trackingx_refsource_REDHAT
https://security.access.redhat.com/data/csaf/v2/v…	x_sadp-csaf-vex
https://access.redhat.com/errata/RHSA-2026:24758	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:24545	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:25051	vendor-advisoryx_refsource_REDHAT

Impacted products

4 products

Vendor	Product	Version
CESNET	libyang	Affected: < SO 5.2.15
Red Hat	Red Hat Enterprise Linux 10	Unaffected: 0:2.1.148-4.el10_2 , < * (rpm) cpe:/o:redhat:enterprise_linux:10.2
Red Hat	Red Hat Enterprise Linux 8	Unaffected: 0:1.0.184-2.el8_10 , < * (rpm) cpe:/a:redhat:enterprise_linux:8
Red Hat	Red Hat Enterprise Linux 9	Unaffected: 0:2.1.148-1.el9_8.1 , < * (rpm) cpe:/a:redhat:enterprise_linux:9

Show details on NVD website

JSON

To clipboard

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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

rlsa-2026:25051

Vulnerability from osv_rocky

CVE-2026-44673 (GCVE-0-2026-44673)

Tags

Sightings

Nomenclature