Vulnerability · CVE-2026-44327
free5GC is an open-source implementation of the 5G core network.
Published May 27, 2026 · catalog updated Oct 14, 2026 · free5GC is an open-source
Check if you run it
No confirmed exploitation is on record for CVE-2026-44327. EPSS is 0.53%. Act only if a listed version of free5GC is an open-source is installed.
Gaps on this record
- The stored product name is a package slug. The name on this page is taken from the title (free5GC is an open-source).
- No version range is stored. A customer cannot check an installed version against this record.
- No vendor fix or required action is stored. Compare the linked advisory before you change production.
- Severity
- Critical10.0
- Known exploitation
- Not in CISA/VulnCheck KEV
- EPSS
- 0.53%
- Remediation
- Advisory link
- Affected products
- cpe free5gc/free5gc
free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF mounts the nnef-oam route group without inbound OAuth2/bearer-token authorization. A network attacker who can reach NEF on the SBI can hit the OAM route with no Authorization header at all and the handler returns 200 OK. The current OAM handler is a stub that returns null, but the structural defect is route-group-scoped: the entire OAM route group has no inbound auth middleware, so every future OAM operation added to this group inherits the missing auth boundary by default. This vulnerability is fixed in 4.2.2.
Are you affected?
Enter the version you run. The result uses only the ranges stored on this record.
The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.
- cpe free5gc/free5gcversion unspecified
How to fix CVE-2026-44327
Recommended remediation
A patch or advisory reference is linked. Open the original publisher for availability by product version.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
No confirmed exploitation is on record for CVE-2026-44327. EPSS is 0.53%. Act only if a listed version of free5GC is an open-source is installed.
Which versions are affected?
Affected version ranges are not on this record. Compare the installed version with the linked vendor advisory before you change production.
What should an analyst verify?
CWE-306: Missing Authentication for Critical Function; CWE-862: Missing Authorization. EPSS 0.53%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Code
The project this record applies to. Exploit listings stay in References.
Timeline
Detection, updates, and resolution for this record.
May 27, 2026 · NIST NVD
Detected
free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF mounts the nnef-oam route group without inbound OAuth2/bearer-token authorization. A network attacker who can reach NEF on the SBI can hit the OAM route with no Authorization header at all and the handler returns 200 OK. The current OAM handler is a stub that returns null, but the structural defect is ro
Oct 14, 2026 · NIST NVD
Updated
free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF mounts the nnef-oam route group without inbound OAuth2/bearer-token authorization. A network attacker who can reach NEF on the SBI can hit the OAM route with no Authorization header at all and the handler returns 200 OK. The current OAM handler is a stub that returns null, but the structural defect is ro
Sources
- CVE.orgVulnerability recordCVE-2026-44327
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2026-44327
30-day exploitation probability 0.5%
first.org - NIST NVDVulnerability recordCVE-2026-44327
free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF mounts the nnef-oam route group without inbound OAuth2/bearer-token authorization. A network attacker who can reach NEF on the SBI can hit the OAM route with no Authorization header at
nvd.nist.gov
References
Freshness
Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.