Missing authorization in free5gc
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- High · Low · None
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-862.
Summary
free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, PCF Npcf_SMPolicyControl missing authentication middleware allows unauthenticated access to SM policy handlers and disclosure of subscriber SUPI. In NewServer(), the smPolicyGroup route group is created and routes are applied without attaching the router authorization middleware. In contrast, other PCF service groups such as Npcf_PolicyAuthorization do attach RouterAuthorizationCheck before route registration. Because the middleware is missing, requests to the /npcf-smpolicycontrol/v1/sm-policies, /npcf-smpolicycontrol/v1/sm-policies/{smPolicyId}, /npcf-smpolicycontrol/v1/sm-policies/{smPolicyId}/update, and /npcf-smpolicycontrol/v1/sm-policies/{smPolicyId}/delete endpoints can reach business logic even when no valid OAuth token is provided. This vulnerability is fixed in 4.2.2.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| free5gc | free5gc | before 4.2.2 | 4.2.2 | Patch available | CNA |
| — | github.com/free5gc/pcf (Go) | before 1.4.3 | 1.4.3 | Patch available | GHSA-6rgm-gr97-x3j5 |
- free5gc Vendorfree5gc Affected before 4.2.2 Fixed in 4.2.2 Patch available CNA
- github.com/free5gc/pcf (Go) Vendor— Affected before 1.4.3 Fixed in 1.4.3 Patch available GHSA-6rgm-gr97-x3j5
Remediation
- Fix · CNA free5gc (free5gc) Fixed in 4.2.2
- Fix · GHSA-6rgm-gr97-x3j5 github.com/free5gc/pcf (Go) Fixed in 1.4.3 Advisory →
Timeline
- 2026-10-02 Threatist record created from CVE-2026-42083
- 2026-10-03 Alias added: GHSA-6rgm-gr97-x3j5
References
Patch 2
Advisory 2
More Free5gc vulnerabilities
- 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
Sources
- CVE-2026-42083 · CVE Program
- CVE-2026-42083 · NVD
- FIRST EPSS
- GHSA-6rgm-gr97-x3j5 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences