CVE-2026-44327

CRITICALNVD 10.010.0
EchelonGraph scoreMEDIUM confidence

Score 10.0 from GitHub Security Advisory (severity: CRITICAL) published 2026-05-08. NVD baseline CVSS 10.0; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
Elevated
10.0
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 0%CVSS: 10.0Exploit: NoneExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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.

CVSS v3
10.0
EG Score
10.0(medium)
EG Risk
76(Attend)
EG Risk 76/100SSVC: Attend

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity100% × 45%
Exploitation40% × 40%
Automatability100% × 15%
Action: Remediate soon — notable exploitation risk.
EPSS
23.4%
KEV
Not listed

Published

May 27, 2026

Last Modified

May 28, 2026

Advisory Details (3)

Auto-updated Jul 22, 2026
🔬 Proof of concept available. Patch available. Sources: github, github_pr.
github Patch Available🟡 PoC Available

NEF nnef-oam route group is unauthenticated; no-token requests reach the OAM handler · Advisory · free5gc/free5gc · GitHub

https://github.com/free5gc/free5gc/security/advisories/GHSA-cmpj-2x3g-m7g3
github_pr

fix(sbi): enforce inbound OAuth2 on NEF service routes

Upstream fix in progress (PR #23 · free5gc/nef, state=closed)

https://github.com/free5gc/nef/pull/23
generic

[Bugs] NEF `nnef-oam` is unauthenticated: no-token requests can access the OAM route · Issue #861 · free5gc/free5gc · GitHub

https://github.com/free5gc/free5gc/issues/861

Vendor Advisories for CVE-2026-44327(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Patch Availability(1)

Vendor / EcosystemFixed in / PatchReleasedSource
gogithub.com/free5gc/nefghsa

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(1 across 1 ecosystem)
Go(1)
PackageVulnerable rangeFixed inDependents
github.com/free5gc/nef

Weakness Classification(2)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 8× in last 7d / 59× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

Showing the most recent 100 of 195 total refreshes for this CVE.

  1. 2026-07-23 03:15 UTCEG score recompute
  2. 2026-07-22 14:08 UTCEPSS rescore
  3. 2026-07-21 15:24 UTCEPSS rescore
  4. 2026-07-20 17:08 UTCEPSS rescore
  5. 2026-07-19 14:31 UTCEPSS rescore
  6. 2026-07-19 02:29 UTCEPSS rescore
  7. 2026-07-18 10:04 UTCEPSS rescore
  8. 2026-07-16 17:03 UTCEPSS rescore
  9. 2026-07-15 16:57 UTCEPSS rescore
  10. 2026-07-15 02:00 UTCEPSS rescore
  11. 2026-07-13 22:30 UTCEPSS rescore
  12. 2026-07-13 06:13 UTCEPSS rescore
  13. 2026-07-12 05:46 UTCEPSS rescore
  14. 2026-07-11 23:17 UTCGHSA enrichment
  15. 2026-07-11 08:27 UTCEPSS rescore
  16. 2026-07-09 19:10 UTCEPSS rescore
  17. 2026-07-08 23:44 UTCGHSA enrichment
  18. 2026-07-08 15:16 UTCEPSS rescore
  19. 2026-07-07 13:46 UTCEPSS rescore
  20. 2026-07-06 16:27 UTCEPSS rescore
  21. 2026-07-06 02:23 UTCEPSS rescore
  22. 2026-07-05 02:30 UTCEPSS rescore
  23. 2026-07-04 06:31 UTCEPSS rescore
  24. 2026-07-03 00:21 UTCGHSA enrichment
  25. 2026-07-01 15:07 UTCEPSS rescore
Show 75 more
  1. 2026-07-01 14:06 UTCGHSA enrichment
  2. 2026-07-01 09:30 UTCGHSA enrichment
  3. 2026-06-30 23:22 UTCEPSS rescore
  4. 2026-06-30 09:08 UTCGHSA enrichment
  5. 2026-06-30 02:46 UTCGHSA enrichment
  6. 2026-06-29 19:47 UTCGHSA enrichment
  7. 2026-06-29 14:06 UTCEPSS rescore
  8. 2026-06-29 14:05 UTCGHSA enrichment
  9. 2026-06-29 01:40 UTCGHSA enrichment
  10. 2026-06-28 21:16 UTCGHSA enrichment
  11. 2026-06-28 16:49 UTCGHSA enrichment
  12. 2026-06-28 14:07 UTCEPSS rescore
  13. 2026-06-28 12:29 UTCGHSA enrichment
  14. 2026-06-28 07:53 UTCGHSA enrichment
  15. 2026-06-28 04:56 UTCEPSS rescore
  16. 2026-06-28 03:34 UTCGHSA enrichment
  17. 2026-06-27 23:12 UTCGHSA enrichment
  18. 2026-06-27 18:43 UTCGHSA enrichment
  19. 2026-06-27 14:23 UTCGHSA enrichment
  20. 2026-06-27 10:03 UTCGHSA enrichment
  21. 2026-06-27 05:43 UTCGHSA enrichment
  22. 2026-06-27 03:08 UTCEPSS rescore
  23. 2026-06-26 21:23 UTCGHSA enrichment
  24. 2026-06-26 17:02 UTCGHSA enrichment
  25. 2026-06-26 02:22 UTCGHSA enrichment
  26. 2026-06-25 21:53 UTCGHSA enrichment
  27. 2026-06-25 17:33 UTCGHSA enrichment
  28. 2026-06-25 13:49 UTCEPSS rescore
  29. 2026-06-25 13:49 UTCEPSS rescore
  30. 2026-06-25 13:13 UTCGHSA enrichment
  31. 2026-06-25 08:53 UTCGHSA enrichment
  32. 2026-06-25 00:24 UTCGHSA enrichment
  33. 2026-06-24 14:05 UTCEPSS rescore
  34. 2026-06-23 21:33 UTCEPSS rescore
  35. 2026-06-22 14:25 UTCEPSS rescore
  36. 2026-06-22 14:25 UTCEPSS rescore
  37. 2026-06-21 14:56 UTCEPSS rescore
  38. 2026-06-21 14:56 UTCEPSS rescore
  39. 2026-06-21 01:59 UTCEPSS rescore
  40. 2026-06-19 19:25 UTCEPSS rescore
  41. 2026-06-18 17:52 UTCEPSS rescore
  42. 2026-06-18 17:52 UTCEPSS rescore
  43. 2026-06-18 03:38 UTCGHSA enrichment
  44. 2026-06-17 22:55 UTCGHSA enrichment
  45. 2026-06-17 18:36 UTCGHSA enrichment
  46. 2026-06-17 17:53 UTCEPSS rescore
  47. 2026-06-17 13:58 UTCGHSA enrichment
  48. 2026-06-17 09:38 UTCGHSA enrichment
  49. 2026-06-17 04:58 UTCGHSA enrichment
  50. 2026-06-17 00:39 UTCGHSA enrichment
  51. 2026-06-16 20:19 UTCGHSA enrichment
  52. 2026-06-16 17:52 UTCEPSS rescore
  53. 2026-06-16 15:59 UTCGHSA enrichment
  54. 2026-06-16 11:14 UTCGHSA enrichment
  55. 2026-06-16 06:54 UTCGHSA enrichment
  56. 2026-06-16 02:35 UTCGHSA enrichment
  57. 2026-06-15 22:15 UTCGHSA enrichment
  58. 2026-06-15 17:49 UTCEPSS rescore
  59. 2026-06-15 13:23 UTCGHSA enrichment
  60. 2026-06-15 06:24 UTCGHSA enrichment
  61. 2026-06-15 02:05 UTCGHSA enrichment
  62. 2026-06-14 21:46 UTCGHSA enrichment
  63. 2026-06-14 17:27 UTCGHSA enrichment
  64. 2026-06-14 13:06 UTCGHSA enrichment
  65. 2026-06-14 08:46 UTCGHSA enrichment
  66. 2026-06-14 04:27 UTCGHSA enrichment
  67. 2026-06-14 00:03 UTCGHSA enrichment
  68. 2026-06-13 23:00 UTCEPSS rescore
  69. 2026-06-13 19:44 UTCGHSA enrichment
  70. 2026-06-13 11:54 UTCGHSA enrichment
  71. 2026-06-13 07:27 UTCGHSA enrichment
  72. 2026-06-13 03:07 UTCGHSA enrichment
  73. 2026-06-12 23:12 UTCEPSS rescore
  74. 2026-06-12 23:12 UTCEPSS rescore
  75. 2026-06-12 22:46 UTCGHSA enrichment

Frequently asked(5)

What is CVE-2026-44327?
CVE-2026-44327 is a critical vulnerability published on May 27, 2026. 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…
When was CVE-2026-44327 disclosed?
CVE-2026-44327 was first published in the National Vulnerability Database on May 27, 2026, with the most recent update on May 28, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-44327 actively exploited?
CVE-2026-44327 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 23.4% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-44327?
CVE-2026-44327 has a CVSS v3 base score of 10.0 (NVD).
How do I remediate CVE-2026-44327?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-44327, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-44327

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