CVE-2026-40246: free5gc UDR improper path validation allows unauthenticated deletion of Traffic Influence Subscriptions

CVE-2026-40246 · Severity: high · CVSS 7.5 · Published 2026-04-16

free5GC is an open-source implementation of the 5G core network. In versions 1.4.2 and below of the UDR service, the handler for deleting 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 deleted regardless. An unauthenticated attacker with access to the 5G Service Based Interface can delete arbitrary Traffic Influence Subscriptions by supplying any value for the influenceId path segment, while the API misleadingly returns a 404 Not Found response. A patched version was not available at the time of publication.

Technologies: github.com/free5gc/udr (Go). Vendors: free5GC, Go.

Quick answers

Is CVE-2026-40246 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-40246 being exploited in the wild.
How severe is CVE-2026-40246?
High severity, with a CVSS score of 7.5, published 16 April 2026.
Which products and versions are affected?
github.com/free5gc/udr (Go) <= 1.4.2, SEMVER:introduced=0, SEMVER:introduced=0,last_affected=1.4.2.
Is there a fix for CVE-2026-40246?
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.
Am I affected by CVE-2026-40246?
Check whether you run free5GC Webconsole or github.com/free5gc/udr (Go) 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.

Affected products

  • free5GC Webconsole
  • github.com/free5gc/udr (Go) <= 1.4.2, SEMVER:introduced=0, SEMVER:introduced=0,last_affected=1.4.2

Identifiers

  • CVE-2026-40246
  • GHSA-g9cw-qwhf-24jp
  • GO-2026-5396

References

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