Vulnerability details

CVE-2026-40248

free5gc free5gc

free5gc UDR improper path validation allows unauthenticated creation and modification of Traffic Influence Subscriptions

CVSS 4.0
8.7High

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.

CVSS scores

ScoreVersionSourceVector
8.7High 4.0 CVEProject cvelistV5 (CNA) (GitHub_M) 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

Affected products

VendorProductVersionsSource
free5gc free5gc <= 1.4.2 CVEProject cvelistV5 (CNA)

References and advisories

1
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Details

Published
2026-04-17
Last updated
2026-04-20
State
Published
Assigner (CNA)
GitHub_M

Exploit prediction (EPSS)

0.42%
Probability of exploitation in 30 days
37%
Percentile (among all CVEs)

SSVC assessment (CISA)

Automatable
Yes
Exploitation
Proof of concept
Technical impact
Partial

Weaknesses (CWE)

  • CWE-285
    Improper Authorization
  • CWE-636
    Not Failing Securely ('Failing Open')