Vulnerability · Published May 27, 2026 · Assigned by GitHub_M

CVE-2026-44326free5GC: NEF 3gpp-traffic-influence API is unauthenticated; missing or forged bearer tokens can create, read, patch, and delete subscriptions

Critical 9.4

In plain English

A critical-severity missing authorization in free5gc from free5gc. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 24% of all known vulnerabilities).

Severity (CVSS 3.1)9.4Critical

Exploit odds (30 days)0.3%top 75.9% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF mounts the 3gpp-traffic-influence API without inbound OAuth2/bearer-token authorization. A network attacker who can reach NEF on the SBI can create, read, patch, and delete traffic-influence subscriptions either with no Authorization header at all, or with a forged bearer token (e.g. Authorization: Bearer not-a-real-token). This includes creating AnyUeInd=true subscriptions intended to affect group / any-UE traffic steering. The route group is also reachable even when the running config's ServiceList does not declare it, so operators who think they disabled the service via config are still exposed. This vulnerability is fixed in 4.2.2.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Go	github.com/free5gc/nef	no fix listed	GHSA-3p28-73q7-45xp
Go	github.com/free5gc/nef	no fix listed	GO-2026-5093

Affected products (as reported)

Vendor	Product	Versions
free5gc	free5gc	< 4.2.2

Weakness: CWE-862 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:H

References

https://github.com/free5gc/free5gc/security/advisories/GHSA-3p28-73q7-45xp x_refsource_CONFIRM
https://github.com/free5gc/free5gc/issues/859 x_refsource_MISC
https://github.com/free5gc/nef/pull/23 x_refsource_MISC