← Vulnerability feed

Vulnerability record · CVE-2026-42081 · published 27 May 2026

CVE-2026-42081: Free5gc vulnerability

Free5gc · Free5gc

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, the AMF in Free5GC does not verify the UE Security Capabilities received in NGAP PathSwitchRequest messages against its locally stored values, as mandated by 3GPP TS 33.501 §6.7.3.1. A malicious gNB can overwrite the AMF's stored UE security capabilities with arbitrary values, which are then propagated in PathSwitchRequest Acknowledge messages and subsequent Handover Request messages. This leads to persistent handover denial-of-service for affected UEs. This vulnerability is fixed in 4.2.2.

7.1 CVSS 3.1 High EPSS 0.28% · top 81.3% CWE-358 · CWE-358
7.1CVSS 3.1 base score
0.28%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
2References, 2 tagged exploit
17 Jun 2026Last modified by NVD

Description

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, the AMF in Free5GC does not verify the UE Security Capabilities received in NGAP PathSwitchRequest messages against its locally stored values, as mandated by 3GPP TS 33.501 §6.7.3.1. A malicious gNB can overwrite the AMF's stored UE security capabilities with arbitrary values, which are then propagated in PathSwitchRequest Acknowledge messages and subsequent Handover Request messages. This leads to persistent handover denial-of-service for affected UEs. This vulnerability is fixed in 4.2.2.

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

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://github.com/free5gc/free5gc/security/advisories/GHSA-77x9-rf64-92gv ExploitVendor Advisory
https://github.com/free5gc/free5gc/security/advisories/GHSA-77x9-rf64-92gv ExploitVendor Advisory

Track CVE-2026-42081 inside VULONE

Watch it alongside the ransomware crews, C2 infrastructure and forum chatter that reference it, query it through the API and pull it into your SIEM over TAXII.

Start free Open in platform

Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

10.0CVE-2026-44327Free5gc missing authentication for critical function vulnerabilityfree5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF mounts the nnef-oam route group without inbound OAuth2…EPSS 0.53%10.0CVE-2026-44329Free5gc missing authentication for critical function vulnerabilityfree5GC 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/b…EPSS 0.56%10.0CVE-2026-44330Free5gc incorrect authorization vulnerabilityfree5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF mounts the nnef-pfdmanagement route group without inbo…EPSS 0.43%9.8CVE-2023-4659Free5gc cross-site request forgery vulnerabilityCross-Site Request Forgery vulnerability, whose exploitation could allow an attacker to perform different actions on the platform as an administrator…EPSS 0.43%9.4CVE-2026-44326Free5gc missing authorization vulnerabilityfree5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF mounts the 3gpp-traffic-influence API without inbound …EPSS 0.53%9.4CVE-2026-44315Free5gc missing authorization vulnerabilityfree5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF mounts the 3gpp-pfd-management API without inbound OAu…EPSS 0.53%8.7CVE-2026-40246Free5gc improper authorization vulnerabilityfree5GC is an open-source implementation of the 5G core network. In versions 1.4.2 and below of the UDR service, the handler for deleting Traffic Inf…EPSS 0.45%8.7CVE-2026-40247Free5gc improper authorization vulnerabilityfree5GC 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 Infl…EPSS 0.51%

Source: NIST National Vulnerability Database (record CVE-2026-42081), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.