# CVE-2026-115327: libyang uninitialized pointer free in NETCONF RPC parsing

Source: https://junglewise.ai/threats/cve-2026-115327-libyang-through-6-4-13-contains-an-uninitialized-pointer-free  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-22. Updated: 2026-10-22  
License: CC BY 4.0 with a link back

CVE-2026-115327 · Severity: medium · CVSS 5.3 · Published 2026-10-22

libyang is a library that parses YANG data models used in network management systems like NETCONF. A vulnerability in the XML parser allows an attacker with a NETCONF session to send a specially crafted RPC action envelope that causes the server to crash or corrupt memory, potentially leading to service outage or code execution.

Technologies: [CESNET Libyang](https://junglewise.ai/threats/technologies/libyang). Vendors: [CESNET](https://junglewise.ai/threats/vendors/cesnet).

## Quick answers

**Is CVE-2026-115327 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-115327 being exploited in the wild.

**How severe is CVE-2026-115327?** Medium severity, with a CVSS score of 5.3, published 22 October 2026.

**Which products and versions are affected?** CESNET Libyang through 6.4.13.

**Is there a fix for CVE-2026-115327?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-115327 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-115327?** Check whether you run CESNET Libyang at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The lydxml_env_netconf_rpc() function in src/parser_xml.c fails to properly initialize a pointer before freeing it when parsing NETCONF RPC action envelopes containing non-whitespace text via lyd_parse_op(). An authenticated peer with an active NETCONF session can trigger this vulnerability to crash the server or corrupt the heap memory.

## Affected products

- CESNET libyang through 6.4.13

## Timeline

- 2026-10-22: disclosed

## References

- [https://github.com/CESNET/libyang](https://github.com/CESNET/libyang)
- [https://github.com/CESNET/libyang/blob/v6.4.13/src/parser_xml.c](https://github.com/CESNET/libyang/blob/v6.4.13/src/parser_xml.c)

## Related threats

- [CESNET libyang heap use-after-free in lyd_parser_set_data_flags](https://junglewise.ai/threats/cve-2026-41401-cesnet-libyang-heap-use-after-free-in-lyd-parser-set-data-flags)
- [CESNET libyang heap buffer overflow in lyb_read_string](https://junglewise.ai/threats/cve-2026-44673-cesnet-libyang-heap-buffer-overflow-in-lyb-read-string)