CVE-2026-44329

CVE-2026-44329 is a critical-severity vulnerability in Free5gc with a CVSS 3.x base score of 10.0. 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-306.

Key facts

Description

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's SMF mounts the UPI management route group without OAuth2/bearer-token authorization middleware. A network attacker who can reach SMF on the SBI can hit UPI endpoints with no Authorization header at all, and the requests reach the SMF business handlers. In the running Docker lab this was directly demonstrated for read (GET /upi/v1/upNodesLinks), write (POST /upi/v1/upNodesLinks with attacker-controlled UP-node and link payload), and delete (DELETE /upi/v1/upNodesLinks/{nodeID}) operations. This vulnerability is fixed in 4.2.2.

Frequently asked questions

What is CVE-2026-44329?
free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's SMF mounts the UPI management route group without OAuth2/bearer-token authorization middleware. A network attacker who can reach SMF on the SBI can hit UPI endpoints with no Authorization header at all, and the requests reach the SMF business handlers. In the running Docker lab this was directly demonstrated for read (GET /upi/v1/upNodesLinks), write (POST /upi/v1/upNodesLinks with attacker-controlled UP-node and link payload), and delete (DELETE /upi/v1/upNodesLinks/{nodeID}) operations. This vulnerability is fixed in 4.2.2.
How severe is CVE-2026-44329?
CVE-2026-44329 has a CVSS 3.x base score of 10.0, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity high, and availability high.
Is CVE-2026-44329 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (25th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-44329?
CVE-2026-44329 affects Free5gc. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-44329?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2026-44329 have an EU (EUVD) identifier?
Yes. CVE-2026-44329 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-32569.
When was CVE-2026-44329 published?
CVE-2026-44329 was published on 2026-05-27 and last updated on 2026-06-17.

References

Affected products (1)

More vulnerabilities in Free5gc

All CVEs affecting Free5gc →

Other CWE-306 (Missing Authentication for Critical Function) vulnerabilities

Browse all CWE-306 (Missing Authentication for Critical Function) vulnerabilities →