CVE-2026-55068
free5GC is an open-source implementation of the 5G core network. In 4.2.2 and earlier, the NRF RegisterNFInstance handler at PUT /nnrf-nfm/v1/nf-instances/{nfInstanceID} accepts NF Profiles without enforcing UUID format, nfStatus enum values, heartBeatTimer ranges, mandatory profile fields, or nfServices.ipEndPoints address constraints. The invalid profiles are persisted in the MongoDB NfProfile collection and returned by NFDiscover, allowing an attacker with SBI access to advertise attacker-controlled network-function endpoints and redirect control-plane signaling. This can expose credentials and signaling, alter service discovery integrity, and deny service across network functions that trust the NRF. This issue is fixed in version 4.2.3.
What this means for your business
- FIRST's prediction model gives it a 0.4% chance of attack attempts being seen in the next 30 days, ranking above 37% of all known flaws.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
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Scoring
- CVSS
- Not yet scored
- CVSS v4
- 9.3
- Weakness
- CWE-20
- Assigned by
- security-advisories@github.com
Dates
- Published
- 2026-08-28
- Last modified
- 2026-09-08
- Sources
- NVD
References
- https://github.com/free5gc/free5gc/issues/1056
- https://github.com/free5gc/free5gc/releases/tag/v4.2.3
- https://github.com/free5gc/free5gc/security/advisories/GHSA-x8mj-6p3q-g5pp
- https://github.com/free5gc/nrf/commit/bda0cf75be5556bb4c758c8b34710f3fe6bbe3ea
- https://github.com/free5gc/nrf/commit/fcd3cfaa27cc4dc17172ee0c4c3e0a3a696297c6
- https://github.com/free5gc/nrf/pull/90
- https://github.com/free5gc/nrf/releases/tag/v1.4.5
- https://github.com/free5gc/free5gc/security/advisories/GHSA-x8mj-6p3q-g5pp