CVE-2026-55513

MEDIUMPre-NVD 5.45.4—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 5.4 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.2%, top 91% 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, secondary
Elevated
5.4EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.4Exploit: Elevated riskExposed: 0

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

nebula-mesh is a self-hosted control plane for Slack Nebula mesh VPN. From version 0.3.0 to before version 0.5.0, the nebula-mgmt Web UI host-creation path ignores both the server-wide enrollment_token_ttl security setting and per-network network_config.enrollment_token_ttl overrides. API host creation and token-regeneration paths use the configured TTL resolver, but POST /ui/hosts hardcodes now.Add(24 * time.Hour) for newly minted agent enrollment tokens. In deployments that intentionally reduce enrollment-token lifetime, any authenticated operator who can create a host through the Web UI can still mint a bearer enrollment token valid for about 24 hours. This issue has been patched in version 0.5.0.

CVSS v3
5.4
EG Score
5.4(medium)
EG Risk
40(Track)
EG Risk 40/100SSVC: 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
Severity54% × 45%
Exploitation40% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
9%
KEV
Not listed

Published

July 14, 2026

Last Modified

September 8, 2026

Advisory Details (3)

Auto-updated Sep 4, 2026
🔬 Proof of concept available. Patch available. Sources: github, github_commit, github_release.
github_release Patch Available

v0.5.0

Patch available: forgekeep/nebula-mesh v0.5.0

https://github.com/forgekeep/nebula-mesh/releases/tag/v0.5.0
github_commit

commit 514006029e09 (forgekeep/nebula-mesh)

Fix landed in forgekeep/nebula-mesh commit 514006029e09 — awaiting tagged release

https://github.com/forgekeep/nebula-mesh/commit/514006029e09f1991122b86a80e7b25970bcfa98
github Patch Available🟡 PoC Available

Web UI host creation ignores configured enrollment token TTL and mints 24-hour bearer enrollment tokens · Advisory · forgekeep/nebula-mesh · GitHub

https://github.com/forgekeep/nebula-mesh/security/advisories/GHSA-g4x6-jcvr-9m3g

Vendor Advisories for CVE-2026-55513(1)

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

Affected Packages

(2 across 1 ecosystem)
Go(2)
PackageVulnerable rangeFixed inDependents
github.com/forgekeep/nebula-mesh—0.5.0—
github.com/juev/nebula-mesh———

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 9× in last 7d / 19× 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 19:28 UTCEPSS rescore
  2. 2026-09-18 04:49 UTCEG score recompute
  3. 2026-09-17 19:31 UTCEPSS rescore
  4. 2026-09-16 14:08 UTCEPSS rescore
  5. 2026-09-16 05:15 UTCEPSS rescore
  6. 2026-09-15 03:11 UTCEPSS rescore
  7. 2026-09-14 08:36 UTCEG score recompute
  8. 2026-09-13 16:47 UTCEPSS rescore
  9. 2026-09-13 07:29 UTCEG score recompute
  10. 2026-09-11 21:52 UTCEG score recompute
  11. 2026-09-11 14:53 UTCEPSS rescore
  12. 2026-09-10 09:35 UTCEPSS rescore
  13. 2026-09-08 22:01 UTCEPSS rescore
  14. 2026-09-08 20:24 UTCEG score recompute
  15. 2026-09-08 01:04 UTCEG score recompute
  16. 2026-09-07 16:01 UTCEPSS rescore
  17. 2026-09-06 13:47 UTCEPSS rescore
  18. 2026-09-05 21:38 UTCEG score recompute
  19. 2026-09-04 20:30 UTCEG score recompute
  20. 2026-07-30 16:13 UTCEG score recompute
  21. 2026-07-26 11:41 UTCEG score recompute
  22. 2026-07-23 03:20 UTCEG score recompute
  23. 2026-07-14 20:56 UTCEG score recompute

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-55513?
CVE-2026-55513 is a medium vulnerability published on July 14, 2026. nebula-mesh is a self-hosted control plane for Slack Nebula mesh VPN. From version 0.3.0 to before version 0.5.0, the nebula-mgmt Web UI host-creation path ignores both the server-wide enrollmenttokenttl security setting and per-network networkconfig.enrollmenttoken_ttl overrides. API host creation…
When was CVE-2026-55513 disclosed?
CVE-2026-55513 was first published in the National Vulnerability Database on July 14, 2026, with the most recent update on September 8, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-55513 actively exploited?
CVE-2026-55513 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 91.4% of all scored CVEs.
What is the CVSS score of CVE-2026-55513?
CVE-2026-55513 has a CVSS v3 base score of 5.4 (NVD).
How do I remediate CVE-2026-55513?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-55513, 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-2026-55513

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