NULL pointer dereference in free5gc
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-476.
Summary
free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF PATCH /3gpp-pfd-management/v1/{afId}/transactions/{transId}/applications/{appId} handler panics with a nil-pointer dereference when the upstream UDR call fails AND the consumer wrapper returns err != nil together with a nil *ProblemDetails. The handler's errPfdData != nil branch builds its own problemDetailsErr correctly, but immediately after it reads problemDetails.Cause (the OTHER value, which is nil in this branch) and panics. Gin recovery converts the panic into HTTP 500, so a single PATCH against this endpoint returns 500 instead of the intended controlled error response whenever UDR access is failing. 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/nef (Go) | before 1.2.3 | 1.2.3 | Patch available | GHSA-j59f-x285-69jx |
- free5gc Vendorfree5gc Affected before 4.2.2 Fixed in 4.2.2 Patch available CNA
- github.com/free5gc/nef (Go) Vendor— Affected before 1.2.3 Fixed in 1.2.3 Patch available GHSA-j59f-x285-69jx
Remediation
- Fix · CNA free5gc (free5gc) Fixed in 4.2.2
- Fix · GHSA-j59f-x285-69jx github.com/free5gc/nef (Go) Fixed in 1.2.3 Advisory →
Timeline
- 2026-10-02 Threatist record created from CVE-2026-44322
- 2026-10-03 Alias added: GHSA-j59f-x285-69jx
- 2026-10-13 EPSS moved to the 50th–90th percentile
- 2026-10-25 EPSS moved to the below the 50th percentile
References
Exploit 2
Patch 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-2026-44322 · CVE Program
- CVE-2026-44322 · NVD
- FIRST EPSS
- GHSA-j59f-x285-69jx · 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