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CVE

CWE

Training

CVE-2026-41401

Published: May 26, 2026

Modified: May 26, 2026

PUBLISHED

CVSS v3.1

6.5

MEDIUM

Description

libyang before 5.2.6 contains a heap use-after-free write vulnerability in lyd_parser_set_data_flags that incorrectly updates metadata list pointers when freeing non-head default metadata entries. Attackers can trigger this vulnerability by submitting crafted YANG XML documents with specific metadata attributes to applications parsing untrusted XML data, causing process crashes or potential code execution.

Vendor	Product	Versions
libyang	libyang	affected `0 - < 5.4.3` unaffected `5.4.3`

Weaknesses (CWE)

CVSS v3.1 Details

CVSS v3.1 Vector

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

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

References

GHSA Advisory GHSA-9f49-8x56-jmjc

vendor-advisory

https://github.com/CESNET/libyang/commit/6b5ed47ee674fbe86b31bbebc4ff26889aeff38c

patch

Anthropic CVD Finding ANT-2026-TZQ1KH7E

third-party-advisory

VulnCheck Advisory: libyang - Heap Use-After-Free Write in XML Metadata Parsing

third-party-advisory

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