CVE-2026-94043: Free5GC Gmm handler.go race condition
A vulnerability was determined in Free5GC up to 4.2.3. This vulnerability affects unknown code of the file /corefuzzerdeps/free5gc/NFs/amf/internal/gmm/handler.go of the component Gmm Handler. This manipulation causes race condition. The attack can be initiated remotely. Patch name: e323b01464355781b8b8d5dd695e05cbc00a62f2. To fix this issue, it is recommended to deploy a patch.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
Free5GCto a version that resolves this vulnerability.Fixed in 4.2.3Patch e323b01464355781b8b8d5dd695e05cbc00a62f2 - Compensating control
Given the attack can be initiated remotely and exploits a race condition in the Gmm handler, restrict network access to the Free5GC AMF/GMM service endpoints (e.g., via firewall/ACL) to trusted sources only until the patch is deployed.
Event History
Frequently Asked Questions
Which deployments are affected?
Free5GC versions up to 4.2.3 are affected. The issue is in the Gmm Handler component, in /corefuzzer_deps/free5gc/NFs/amf/internal/gmm/handler.go.
Does exploitation require authentication or user interaction?
No authentication or user interaction is indicated. The vulnerability can be initiated remotely and has low attack complexity.
What is the recommended remediation?
Deploy the patch identified as e323b01464355781b8b8d5dd695e05cbc00a62f2. The provided information does not specify an alternative mitigation if patching cannot be performed immediately.