CVE-2026-61699

HIGHPre-NVD 8.18.1—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 8.1 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.2%, top 83% 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
8.1EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 8.1Exploit: 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. Prior to version 0.7.1, revocation is the only in-band mechanism that isolates a compromised/offboarded host from a Nebula mesh. Because the blocklist never reaches any peer's config.yml, a Blocked host retains full overlay reachability to every peer under its CA (and internal services on the mesh) for up to 30d (agent) / 365d (mobile). An attacker who exfiltrates host.key+host.crt can run stock slackhq/nebula directly, ignore the agent's 403/410 poll responses, and stay connected after the operator revokes the host. Operator-visible state (UI shows blocked, audit log records it) is misleading. This issue has been patched in version 0.7.1.

CVSS v3
8.1
EG Score
8.1(medium)
EG Risk
52(Track*)
EG Risk 52/100SSVC: 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
Severity81% × 45%
Exploitation40% × 40%
Automatability0% × 15%
Action: Watch closely — could escalate to Attend.
EPSS PROB
0%
EPSS %ILE
17%
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_release, github, github_commit.
github_release Patch Available

v0.7.1

Patch available: forgekeep/nebula-mesh v0.7.1

https://github.com/forgekeep/nebula-mesh/releases/tag/v0.7.1
github_commit

commit 0426e2f224a9 (forgekeep/nebula-mesh)

Fix landed in forgekeep/nebula-mesh commit 0426e2f224a9 — awaiting tagged release

https://github.com/forgekeep/nebula-mesh/commit/0426e2f224a9b1e2029029bf923c93ed39d21cdb
github Patch Available🟡 PoC Available

Certificate revocation is never enforced at the mesh: nebula-agent drops the polled blocklist and the generated config.yml has no pki.blocklist, so blocked/compromised hosts keep full mesh access until their cert expires (up to 30d agent / 365d mobile) · Advisory · forgekeep/nebula-mesh · GitHub

https://github.com/forgekeep/nebula-mesh/security/advisories/GHSA-cm26-5974-52h8

Vendor Advisories for CVE-2026-61699(1)

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

Affected Packages

(1 across 1 ecosystem)
Go(1)
PackageVulnerable rangeFixed inDependents
github.com/forgekeep/nebula-mesh—0.7.1—

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 6× in last 7d / 17× 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. 2026-09-16 14:08 UTCEPSS rescore
  4. 2026-09-16 05:15 UTCEPSS rescore
  5. 2026-09-13 23:15 UTCEG score recompute
  6. 2026-09-13 07:29 UTCEG score recompute
  7. 2026-09-11 21:52 UTCEG score recompute
  8. 2026-09-11 14:53 UTCEPSS rescore
  9. 2026-09-11 09:37 UTCEPSS rescore
  10. 2026-09-08 22:01 UTCEPSS rescore
  11. 2026-09-08 16:13 UTCEG score recompute
  12. 2026-09-08 13:07 UTCEG score recompute
  13. 2026-09-08 01:04 UTCEG score recompute
  14. 2026-09-07 16:01 UTCEPSS rescore
  15. 2026-09-06 13:47 UTCEPSS rescore
  16. 2026-09-05 20:55 UTCEG score recompute
  17. 2026-09-04 20:30 UTCEG score recompute
  18. 2026-07-30 19:02 UTCEG score recompute
  19. 2026-07-26 11:41 UTCEG score recompute
  20. 2026-07-23 03:21 UTCEG score recompute
  21. 2026-07-14 20:56 UTCEG score recompute

Frequently asked(5)

What is CVE-2026-61699?
CVE-2026-61699 is a high vulnerability published on July 14, 2026. nebula-mesh is a self-hosted control plane for Slack Nebula mesh VPN. Prior to version 0.7.1, revocation is the only in-band mechanism that isolates a compromised/offboarded host from a Nebula mesh. Because the blocklist never reaches any peer's config.yml, a Blocked host retains full overlay…
When was CVE-2026-61699 disclosed?
CVE-2026-61699 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-2026-61699 actively exploited?
CVE-2026-61699 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 83.4% of all scored CVEs.
What is the CVSS score of CVE-2026-61699?
CVE-2026-61699 has a CVSS v3 base score of 8.1 (NVD).
How do I remediate CVE-2026-61699?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-61699, 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-2026-61699

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