How severe is CVE-2026-40247?

CVE-2026-40247 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2026-40247 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (39th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-40247?

CVE-2026-40247 affects Free5gc. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-40247?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-40247 have an EU (EUVD) identifier?

Yes. CVE-2026-40247 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-23312.

When was CVE-2026-40247 published?

CVE-2026-40247 was published on 2026-04-16 and last updated on 2026-06-17.

CVE-2026-40247

CVE-2026-40247 is a high-severity vulnerability in Free5gc with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-285.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v4: 8.7
EPSS exploit prediction: 0% (39th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-23312
Weakness: CWE-285
Affected product: Free5gc
Published: 2026-04-16
Last modified: 2026-06-17

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 reading 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 data is returned alongside the 404 response. An unauthenticated attacker with access to the 5G Service Based Interface can read arbitrary Traffic Influence Subscriptions, including SUPIs/IMSIs, DNNs, S-NSSAIs, and callback URIs, by supplying any value for the influenceId path segment. A patched version was not available at the time of publication.

Frequently asked questions

What is CVE-2026-40247?: 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 reading 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 data is returned alongside the 404 response. An unauthenticated attacker with access to the 5G Service Based Interface can read arbitrary Traffic Influence Subscriptions, including SUPIs/IMSIs, DNNs, S-NSSAIs, and callback URIs, by supplying any value for the influenceId path segment. A patched version was not available at the time of publication.
How severe is CVE-2026-40247?: CVE-2026-40247 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2026-40247 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (39th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-40247?: CVE-2026-40247 affects Free5gc. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-40247?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-40247 have an EU (EUVD) identifier?: Yes. CVE-2026-40247 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-23312.
When was CVE-2026-40247 published?: CVE-2026-40247 was published on 2026-04-16 and last updated on 2026-06-17.

References

https://github.com/free5gc/free5gc/security/advisories/GHSA-x5r2-r74c-3w28

Affected products (1)

cpe:2.3:a:free5gc:free5gc:*:*:*:*:*:*:*:*

More vulnerabilities in Free5gc

CVE-2026-44330 — Critical (CVSS 10.0): free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF mounts the…
CVE-2026-44329 — Critical (CVSS 10.0): free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's SMF mounts the UPI…
CVE-2026-44327 — Critical (CVSS 10.0): free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF mounts the nnef-oam…
CVE-2023-4659 — Critical (CVSS 9.8): Cross-Site Request Forgery vulnerability, whose exploitation could allow an attacker to perform different actions on…
CVE-2026-44326 — Critical (CVSS 9.4): free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF mounts the…
CVE-2026-44315 — Critical (CVSS 9.4): free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF mounts the…

All CVEs affecting Free5gc →

Other CWE-285 (Improper Authorization) vulnerabilities

CVE-2025-65041 — Critical (CVSS 10.0): Improper authorization in Microsoft Partner Center allows an unauthorized attacker to elevate privileges over a network.
CVE-2023-33189 — Critical (CVSS 10.0): Pomerium is an identity and context-aware access proxy. With specially crafted requests, incorrect authorization…
CVE-2022-2595 — Critical (CVSS 10.0): Improper Authorization in GitHub repository kromitgmbh/titra prior to 0.79.1.
CVE-2021-28799 — Critical (CVSS 10.0): An improper authorization vulnerability has been reported to affect QNAP NAS running HBS 3 (Hybrid Backup Sync. ) If…
CVE-2026-34048 — Critical (CVSS 9.9): Coolify is an open-source and self-hostable tool for managing servers, applications, and databases. Prior to…
CVE-2026-5412 — Critical (CVSS 9.9): In Juju versions prior to 2.9.57 and 3.6.21, an authorization issue exists in the Controller facade. An authenticated…

Browse all CWE-285 (Improper Authorization) vulnerabilities →