CVE-2026-53551 | BDVDB-2026-354429 Detail
free5gcfree5gc
Description#
free5GC is an open-source implementation of the 5G core network. Prior to 1.4.5, the free5GC AUSF (Authentication Server Function) does not validate the supiOrSuci field in UE authentication requests. Null bytes (\x00) and other control characters pass through JSON parsing unchanged and are forwarded to the UDM in an unescaped URL path. This causes Go's net/url.Parse() to fail, returning HTTP 500 "System failure" and leaking internal stack traces. An unauthenticated attacker can trigger this at scale causing denial of service for all subscribers attempting authentication through the affected AUSF. This vulnerability is fixed in 1.4.5.
Impact#
Per CVSS v4.0: confidentiality impact none, integrity impact none, availability impact low. Attack vector: network.
Weaknesses#
- CWE-20 Improper Input Validation
References#
- https://github.com/free5gc/free5gc/security/advisories/GHSA-qj55-47fp-p62j
- https://github.com/free5gc/free5gc/issues/1048
- https://github.com/free5gc/ausf/pull/61
- https://github.com/free5gc/ausf/commit/bfc4a10094dbacbd862baa4686829f3fcc06ce1e
- https://github.com/free5gc/ausf/releases/tag/v1.4.5
- https://github.com/free5gc/free5gc/releases/tag/v4.2.2
Exploit#
No public exploit known
History#
- Version 1Record published in the CVE List.
- Version 2Most recent update recorded in the CVE List.