Vulnerability · Published Apr 16, 2026 · Assigned by GitHub_M
CVE-2026-40248free5gc UDR improper path validation allows unauthenticated creation and modification of 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 0.4% (higher than 37% 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 creating or updating 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 is created or overwritten regardless. An unauthenticated attacker with access to the 5G Service Based Interface can create or overwrite arbitrary Traffic Influence Subscriptions, including injecting attacker-controlled notificationUri values and arbitrary SUPIs, 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-jgq2-qv8v-5cmj |
| Go | github.com/free5gc/udr | no fix listed | GO-2026-5470 |
Affected products (as reported)
Weakness: CWE-285, CWE-636 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
References
- https://github.com/free5gc/free5gc/security/advisories/GHSA-jgq2-qv8v-5cmj x_refsource_CONFIRM