free5GC: NRF POST /oauth2/token structured-form parser type-confusion panic family (Reflect.Set on incompatible types)
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-843 and the CVSS impact.
Summary
free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NRF root SBI endpoint POST /oauth2/token contains a parser-level type-confusion bug family. The handler in NFs/nrf/internal/sbi/api_accesstoken.go reflects over models.NrfAccessTokenAccessTokenReq, special-cases only plain string and NrfNfManagementNfType fields, and treats every other field as if it were a single models.PlmnId. The parsed *models.PlmnId is then assigned with reflect.Value.Set() to whichever field name the attacker put in the form body, which panics whenever the destination field's real type is incompatible (slice, different struct, primitive). Gin recovery converts each panic into HTTP 500, but the endpoint remains remotely panicable from a single unauthenticated form-encoded request and is repeatedly triggerable. 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/nrf (Go) | before 1.4.3 | 1.4.3 | Patch available | GHSA-f8qv-7x5w-qr48 |
- free5gc Vendorfree5gc Affected before 4.2.2 Fixed in 4.2.2 Patch available CNA
- github.com/free5gc/nrf (Go) Vendor— Affected before 1.4.3 Fixed in 1.4.3 Patch available GHSA-f8qv-7x5w-qr48
Remediation
- Fix · CNA free5gc (free5gc) Fixed in 4.2.2
- Fix · GHSA-f8qv-7x5w-qr48 github.com/free5gc/nrf (Go) Fixed in 1.4.3 Advisory →
Timeline
- 2026-10-02 Threatist record created from CVE-2026-44325
- 2026-10-03 Alias added: GHSA-f8qv-7x5w-qr48
- 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-2026-44325 · CVE Program
- CVE-2026-44325 · NVD
- FIRST EPSS
- GHSA-f8qv-7x5w-qr48 · 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