CVE-2026-27643

MEDIUMNVD 5.35.3—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 5.3 under NVD CVSS v3. EPSS exploit probability: 0.3%, top 80% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, nvd
5.3EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.3Exploit: None knownExposed: 0

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

free5GC UDR is the user data repository (UDR) for free5GC, an an open-source project for 5th generation (5G) mobile core networks. In versions up to and including 1.4.1, the NEF component reliably leaks internal parsing error details (e.g., invalid character 'n' after top-level value) to remote clients, which can aid attackers in service fingerprinting. All deployments of free5GC using the Nnef_PfdManagement service may be affected. free5gc/udr pull request 56 contains a patch for the issue. There is no direct workaround at the application level. The recommendation is to apply the provided patch.

CVSS v3
5.3
EG Score
5.3(medium)
EG Risk
28(Track)
EG Risk 28/100SSVC: Track

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
Severity53% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
20%
KEV
Not listed

Published

February 24, 2026

Last Modified

June 17, 2026

Advisory Details (4)

Auto-updated Aug 4, 2026
Patch available. Sources: github, github_commit, github_pr.
github_pr Patch Available

fix: add missing return statements after error responses

Patch available: free5gc/udr v1.4.2 (PR #56 merged 2026-01-12)

https://github.com/free5gc/udr/pull/56
github_commit Patch Available

commit 754d23b03755 (free5gc/udr)

Patch available: free5gc/udr v1.4.2 (contains commit 754d23b03755)

https://github.com/free5gc/udr/commit/754d23b03755ad59077ed529ce3b971e477080c4
github Patch Available

Improper error handling in NEF with information exposure · Advisory · free5gc/free5gc · GitHub

https://github.com/free5gc/free5gc/security/advisories/GHSA-6468-f87j-6g82
generic

[Bugs] NEF incorrectly returns 500 for missing PFD data (UDR 404) in Nnef_PfdManagement GET request (JSON parse error: invalid character 'n') · Issue #753 · free5gc/free5gc · GitHub

https://github.com/free5gc/free5gc/issues/753

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 7× in last 7d / 28× 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.

  1. 2026-09-18 19:36 UTCOSV refresh
  2. 2026-09-18 19:28 UTCEPSS rescore
  3. 2026-09-18 19:27 UTCEPSS rescore
  4. 2026-09-17 19:30 UTCEPSS rescore
  5. 2026-09-16 14:08 UTCEPSS rescore
  6. 2026-09-16 05:15 UTCEPSS rescore
  7. 2026-09-13 16:47 UTCEPSS rescore
  8. 2026-09-12 15:01 UTCEPSS rescore
  9. 2026-09-11 14:52 UTCEPSS rescore
  10. 2026-09-10 09:34 UTCEPSS rescore
  11. 2026-09-08 22:00 UTCEPSS rescore
  12. 2026-09-07 16:01 UTCEPSS rescore
  13. 2026-09-06 13:47 UTCEPSS rescore
  14. 2026-09-06 13:47 UTCEPSS rescore
  15. 2026-09-04 05:06 UTCEPSS rescore
  16. 2026-09-02 14:11 UTCEPSS rescore
  17. 2026-09-01 13:53 UTCEPSS rescore
  18. 2026-09-01 04:39 UTCEPSS rescore
  19. 2026-08-30 22:47 UTCOSV refresh
  20. 2026-08-30 19:17 UTCEPSS rescore
  21. 2026-08-30 01:22 UTCEPSS rescore
  22. 2026-08-28 21:41 UTCEPSS rescore
  23. 2026-08-27 14:25 UTCEPSS rescore
  24. 2026-08-26 14:46 UTCEPSS rescore
  25. 2026-08-25 13:48 UTCEPSS rescore
Show 35 more
  1. 2026-08-23 00:19 UTCEPSS rescore
  2. 2026-08-21 23:49 UTCEPSS rescore
  3. 2026-08-20 22:55 UTCEPSS rescore
  4. 2026-08-19 17:03 UTCEPSS rescore
  5. 2026-08-18 13:48 UTCEPSS rescore
  6. 2026-08-17 13:47 UTCEPSS rescore
  7. 2026-08-16 14:56 UTCEPSS rescore
  8. 2026-08-16 02:14 UTCEPSS rescore
  9. 2026-08-15 01:30 UTCEPSS rescore
  10. 2026-08-14 09:10 UTCEG score recompute
  11. 2026-08-13 22:00 UTCEPSS rescore
  12. 2026-08-13 01:36 UTCEG score recompute
  13. 2026-08-12 13:50 UTCEPSS rescore
  14. 2026-08-12 01:00 UTCEG score recompute
  15. 2026-08-11 13:42 UTCEPSS rescore
  16. 2026-08-11 00:00 UTCEPSS rescore
  17. 2026-08-10 09:23 UTCEG score recompute
  18. 2026-08-09 13:46 UTCEPSS rescore
  19. 2026-08-09 08:47 UTCEG score recompute
  20. 2026-08-08 16:37 UTCEPSS rescore
  21. 2026-08-07 20:56 UTCEG score recompute
  22. 2026-08-06 13:46 UTCEPSS rescore
  23. 2026-08-06 03:10 UTCEG score recompute
  24. 2026-08-05 19:17 UTCEPSS rescore
  25. 2026-08-04 15:10 UTCEPSS rescore
  26. 2026-08-04 06:01 UTCEG score recompute
  27. 2026-08-03 10:36 UTCEPSS rescore
  28. 2026-08-02 19:44 UTCEG score recompute
  29. 2026-08-02 02:26 UTCEPSS rescore
  30. 2026-08-01 04:16 UTCEPSS rescore
  31. 2026-07-30 16:27 UTCEPSS rescore
  32. 2026-07-30 01:30 UTCEPSS rescore
  33. 2026-07-28 15:36 UTCEPSS rescore
  34. 2026-07-27 14:09 UTCEG score recompute
  35. 2026-07-27 13:57 UTCOSV refresh

Frequently asked(5)

What is CVE-2026-27643?
CVE-2026-27643 is a medium vulnerability published on February 24, 2026. free5GC UDR is the user data repository (UDR) for free5GC, an an open-source project for 5th generation (5G) mobile core networks. In versions up to and including 1.4.1, the NEF component reliably leaks internal parsing error details (e.g., invalid character 'n' after top-level value) to remote…
When was CVE-2026-27643 disclosed?
CVE-2026-27643 was first published in the National Vulnerability Database on February 24, 2026, with the most recent update on June 17, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-27643 actively exploited?
CVE-2026-27643 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 79.8% of all scored CVEs.
What is the CVSS score of CVE-2026-27643?
CVE-2026-27643 has a CVSS v3 base score of 5.3 (NVD).
How do I remediate CVE-2026-27643?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-27643, 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

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