CVE-2026-40245: high-severity vulnerability in free5gc
Free5GC: UDR nudr-dr influenceData/subs-to-notify leaks SUPI in error response body without authentication
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21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 7.5epss 0.5%
Free5GC is an open-source Linux Foundation project for 5th generation (5G) mobile core networks. Versions 4.2.1 and below contain an information disclosure vulnerability in the UDR (Unified Data Repository) service. The handler for GET /nudr-dr/v2/application-data/influenceData/subs-to-notify sends an HTTP 400 error response when required query parameters are missing but does not return afterward. Execution continues into the processor function, which queries the data repository and appends the full list of Traffic Influence Subscriptions, including SUPI/IMSI values, to the response body. An unauthenticated attacker with network access to the 5G Service Based Interface can retrieve stored subscriber identifiers with a single parameterless HTTP GET request. The SUPI is the most sensitive subscriber identifier in 5G networks, and its exposure undermines the privacy guarantees of the 3GPP SUCI concealment mechanism at the core network level. A similar bypass exists when sending a malformed snssai parameter due to the same missing return pattern.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Affected products
free5gc · free5gcRelated CVEs — free5gc
In the same product, most dangerous first.
CVE-2026-53551MEDIUMfree5GC AUSF: null byte injection in supiOrSuci causes HTTP 500 internal service failureEPSS 0.7%CVE-2026-55068CRITICALfree5GC: NRF nnrf-nfm lacks NF Profile input validation — enables NF Registration Poisoning with arbitrary service endpointsEPSS 0.6%CVE-2026-47780MEDIUMfree5GC: UDR Improper ueId validation in free5GC EE subscription handlers allows arbitrary identifier persistenceEPSS 0.5%CVE-2026-33064HIGHfree5GC UDM DataChangeNotification Procedure Panic Due to Nil Pointer DereferenceEPSS 0.5%CVE-2026-40247HIGHfree5gc UDR improper path validation allows unauthenticated access to Traffic Influence SubscriptionsEPSS 0.5%CVE-2026-55785LOWfree5GC AUSF uses non-constant-time authentication comparisons and logs XRES* in 5G-AKAEPSS 0.4%