CVE-2026-41401: libyang Use After Free

Vulnerability summary

CVE-2026-41401 is a high (CVSS 7.1) Use After Free vulnerability in libyang. EPSS estimates a 0.64% chance of exploitation in the next 30 days, higher than 50% of scored vulnerabilities.

Timeline

1. 26-05-2026
   PublishedVulnerability first disclosed.
2. 26-05-2026
   Last modifiedVulnerability information updated.

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.

• CWE-416Use After FreeThe product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.