CVE-2026-40245: Free5gc information disclosure (CVSS 7.5)

Description

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 breakdown

Attack vectorNetwork

Attack complexityLow

Privileges requiredNone

User interactionNone

ScopeUnchanged

ConfidentialityHigh

IntegrityNone

AvailabilityNone

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Affected products

Free5gc≤ 4.2.1

Remediation

No fixed version is recorded in the NVD data. Check the vendor advisory for the latest guidance.

References

https://github.com/free5gc/free5gc/security/advisories/GHSA-wrwh-rpq4-87hfExploitThird Party Advisory

Related CVEs

Recent high-severity vulnerabilities sharing a weakness type.

Frequently asked

Is CVE-2026-40245 being actively exploited?

CVE-2026-40245 is not in the CISA KEV catalog. A public exploit reference exists, so treat it as exploitable. Its EPSS exploit probability is 0.56%.

How severe is CVE-2026-40245?

CVE-2026-40245 has a CVSS 3.1 base score of 7.5, rated high. EPSS estimates a 0.56% probability of exploitation.

Which products are affected by CVE-2026-40245?

Affected products include Free5gc.

How do I fix CVE-2026-40245?

Apply the vendor's patch or advisory guidance, then verify no affected versions remain across your devices.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2026-40245 against the real software inventory on every managed device, every day. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

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