Vulnerability · Published Apr 16, 2026 · Assigned by GitHub_M
CVE-2026-40247free5gc UDR improper path validation allows unauthenticated access to Traffic Influence Subscriptions
High 8.7
In plain English
A high-severity security flaw in free5gc from free5gc. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 43% of all known vulnerabilities).
Official description
free5GC is an open-source implementation of the 5G core network. In versions 4.2.1 and below of the UDR service, the handler for reading Traffic Influence Subscriptions checks whether the influenceId path segment equals subs-to-notify, but does not return after sending the HTTP 404 response when validation fails. Execution continues and the subscription data is returned alongside the 404 response. An unauthenticated attacker with access to the 5G Service Based Interface can read arbitrary Traffic Influence Subscriptions, including SUPIs/IMSIs, DNNs, S-NSSAIs, and callback URIs, by supplying any value for the influenceId path segment. A patched version was not available at the time of publication.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Go | github.com/free5gc/udr | no fix listed | GHSA-x5r2-r74c-3w28 |
| Go | github.com/free5gc/udr | no fix listed | GO-2026-5741 |
Affected products (as reported)
Weakness: CWE-285, CWE-636 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
References
- https://github.com/free5gc/free5gc/security/advisories/GHSA-x5r2-r74c-3w28 x_refsource_CONFIRM