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TI-2026-30449 Aliases CVE-2026-42081GHSA-77x9-rf64-92gv

free5GC: UE Security Capability bypass on NGAP PathSwitchRequest

Priority MEDIUM 64CWE-358Published · Updated

Key facts

Attack vector
Adjacent network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · Low · High
Fix status
Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and GitHub.

Summary

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00266 18th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed free5gc (free5gc): 4.2.2

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
free5gcfree5gcbefore 4.2.24.2.2Patch availableCNA
—github.com/free5gc/amf (Go)up to 1.4.3—No fix listedGHSA-77x9-rf64-92gv
  • free5gc Vendorfree5gc Affected before 4.2.2 Fixed in 4.2.2 Patch available CNA
  • github.com/free5gc/amf (Go) Vendor— Affected up to 1.4.3 Fixed in — No fix listed GHSA-77x9-rf64-92gv

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:free5gc:free5gc:*:*:*:*:*:*:*:*before 4.2.2Vulnerablefree5gc
  • cpe:2.3:a:free5gc:free5gc:*:*:*:*:*:*:*:* Versions before 4.2.2 Vulnerable ·free5gc

Remediation

  • Fix · CNA free5gc (free5gc) Fixed in 4.2.2

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-42081
  2. 2026-10-03 Alias added: GHSA-77x9-rf64-92gv

References

Exploit 1

Advisory 1

Other 2

  • TI-2026-32298 Incorrect authorization in free5gc CVSS 3.1CRITICAL 10.0
  • TI-2026-32297 free5GC: SMF UPI management interface lacks auth middleware; unauthenticated topology read/write requests reach handlers CVSS 3.1CRITICAL 10.0
  • TI-2026-32295 free5GC: NEF nnef-oam route group is unauthenticated; no-token requests reach the OAM handler CVSS 3.1CRITICAL 10.0
  • TI-2025-39412 free5gc v4.1.0 and before is vulnerable to Buffer Overflow. CVSS 3.1CRITICAL 9.8
  • TI-2026-32294 Missing authorization in free5gc CVSS 3.1CRITICAL 9.4
  • TI-2026-32283 Missing authorization in free5gc CVSS 3.1CRITICAL 9.4
See all 58 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences