CVE-2026-41401
MediumCVSS 6.5Exploitation Probability (EPSS)
Elevated risk52th percentile - higher than 52% of all known CVEs
Summary
libyang before 5.4.3 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 it by submitting crafted YANG XML documents with specific metadata attributes to applications parsing untrusted XML data.
Risk Assessment
An attacker can cause a process crash or potential code execution by submitting a malicious XML document to an application using libyang. The risk affects services parsing untrusted YANG XML data.
Recommendation
Update libyang to version 5.4.3 or later. Validate and restrict untrusted XML data submitted to applications.
Other vulnerabilities in libyang
See all- CVE-2026-115327Medium
libyang through 6.4.13 contains an uninitialized pointer free vulnerability in lydxml_env_netconf_rpc() in src/parser_xml.c when parsing NETCONF rpc action envelopes. Peers with a NETCONF session can send an action element containing non-whitespace text via lyd_parse_op() to crash servers like netopeer2 or corrupt the heap.
- CVE-2026-44673High
In libyang library prior to SO 5.2.15, an integer overflow in lyb_read_string() in src/parser_lyb.c leads to 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.
Original NVD description (English source)
libyang before 5.4.3 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.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS