CVE-2026-27643

Name: CVE-2026-27643
Creator: NVD / NIST
Published: 2026-02-24T01:16:15.543+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.6/10EPSS 0.27%

Last modified Jun 17, 2026

CVE-2026-27643 is a medium-severity vulnerability rated 6.6/10 on the CVSS scale. free5GC UDR is the user data repository (UDR) for free5GC, an an open-source project for 5th generation (5G) mobile core networks. In versions up to and including 1.4.1, the NEF component reliably leaks internal parsing error details (e.g., invalid character 'n' after top-level value) to remote clients, which can aid attackers in service fingerprinting. EPSS estimates a 0.27% chance of exploitation in the next 30 days.

Description

free5GC UDR is the user data repository (UDR) for free5GC, an an open-source project for 5th generation (5G) mobile core networks. In versions up to and including 1.4.1, the NEF component reliably leaks internal parsing error details (e.g., invalid character 'n' after top-level value) to remote clients, which can aid attackers in service fingerprinting. All deployments of free5GC using the Nnef_PfdManagement service may be affected. free5gc/udr pull request 56 contains a patch for the issue. There is no direct workaround at the application level. The recommendation is to apply the provided patch.

Metrics

CVSS 3.1

5.3/10

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

CVSS 4.0

6.6/10

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

EPSS Probability

0.27%

19.2th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-209

Affected Software

Vendor	Product	Versions
Free5gc	Udr	<= 1.4.1

References

https://github.com/free5gc/free5gc/issues/753Exploit, Issue Tracking, Patch, Vendor Advisory
https://github.com/free5gc/free5gc/security/advisories/GHSA-6468-f87j-6g82Patch, Vendor Advisory
https://github.com/free5gc/udr/commit/754d23b03755ad59077ed529ce3b971e477080c4Patch
https://github.com/free5gc/udr/pull/56Issue Tracking, Patch

Timeline

Published: Feb 24, 2026
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2026-27643?

How severe is CVE-2026-27643?

CVE-2026-27643 has a CVSS score of 6.6/10 (MEDIUM severity). The EPSS model estimates a 0.27% probability of exploitation in the next 30 days.

How do I fix CVE-2026-27643?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2026-27643?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST