CVE-2026-18638

MEDIUMPre-NVD 6.56.5—
EchelonGraph scoreHIGH confidence

Score 6.5 from GitHub Security Advisory published 2026-08-11. a secondary CVSS source baseline 6.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 3 sources updated this week
6.5EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 6.5Exploit: None knownExposed: 0

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

Any authenticated Velociraptor user — including one holding only the readerrole — can terminate the entire server process with a single request, by calling SetPassword with a username that does not exist.

CVSS v3
6.5
EG Score
6.5(high)
EG Risk
29(Track)
EG Risk 29/100SSVC: 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
Severity65% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
22%
KEV
Not listed

Published

August 11, 2026

Last Modified

August 11, 2026

Advisory Details (1)

Auto-updated Aug 11, 2026
No patch confirmed yet.
generic

CVE-2026-18638 Velociraptor server crash via the SetPassword API

http://docs.velociraptor.app/announcements/advisories/cve-2026-18638/

Vendor Advisories for CVE-2026-18638(1)

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

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 20× in last 7d / 31× 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. 2026-08-20 22:55 UTCEPSS rescore
  2. 2026-08-20 19:29 UTCGHSA enrichment
  3. 2026-08-19 19:25 UTCEG score recompute
  4. 2026-08-19 19:25 UTCGHSA enrichment
  5. 2026-08-19 17:03 UTCEPSS rescore
  6. 2026-08-18 19:21 UTCEG score recompute
  7. 2026-08-18 19:21 UTCGHSA enrichment
  8. 2026-08-18 13:48 UTCEPSS rescore
  9. 2026-08-17 19:17 UTCEG score recompute
  10. 2026-08-17 19:17 UTCGHSA enrichment
  11. 2026-08-17 13:47 UTCEPSS rescore
  12. 2026-08-16 18:59 UTCEG score recompute
  13. 2026-08-16 18:59 UTCGHSA enrichment
  14. 2026-08-16 14:56 UTCEPSS rescore
  15. 2026-08-16 02:14 UTCEPSS rescore
  16. 2026-08-15 18:55 UTCEG score recompute
  17. 2026-08-15 18:55 UTCGHSA enrichment
  18. 2026-08-15 01:30 UTCEPSS rescore
  19. 2026-08-14 18:51 UTCEG score recompute
  20. 2026-08-14 18:51 UTCGHSA enrichment
  21. 2026-08-13 22:00 UTCEPSS rescore
  22. 2026-08-13 18:47 UTCGHSA enrichment
  23. 2026-08-12 18:43 UTCEG score recompute
  24. 2026-08-12 18:43 UTCGHSA enrichment
  25. 2026-08-12 13:50 UTCEPSS rescore
Show 6 more
  1. 2026-08-11 18:39 UTCEG score recompute
  2. 2026-08-11 18:39 UTCGHSA enrichment
  3. 2026-08-11 17:45 UTCEG score recompute
  4. 2026-08-11 16:36 UTCEG score recompute
  5. 2026-08-11 15:21 UTCEG score recompute
  6. 2026-08-11 15:20 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-18638?
CVE-2026-18638 is a medium vulnerability published on August 11, 2026. Any authenticated Velociraptor user — including one holding only the readerrole — can terminate the entire server process with a single request, by calling SetPassword with a username that does not exist.
When was CVE-2026-18638 disclosed?
CVE-2026-18638 was first published in the National Vulnerability Database on August 11, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-18638 actively exploited?
CVE-2026-18638 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 78.5% of all scored CVEs.
What is the CVSS score of CVE-2026-18638?
CVE-2026-18638 has a CVSS v3 base score of 6.5 (NVD).
How do I remediate CVE-2026-18638?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-18638, 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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