CVE-2026-18654

MEDIUMPre-NVD 6.86.8
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 6.8 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.3%, top 78% 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
6.8EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 6.8Exploit: None knownExposed: 0

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

Key exchange without entity authentication in the EMR SSH helper commands in Amazon AWS CLI before 1.45.28 and AWS CLI v2 before 2.35.3 might allow man-in-the-middle attackers to intercept SSHsessions and file transfers via network positioning between the client and the EMR cluster endpoint.

To remediate this issue, users should upgrade to AWS CLI v1 1.45.28 or later, or AWS CLI v2 2.35.3 or later.

CVSS v3
6.8
EG Score
6.8(medium)
EG Risk
31(Track)
EG Risk 31/100SSVC: 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
Severity68% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
22%
KEV
Not listed

Published

August 3, 2026

Last Modified

August 4, 2026

Advisory Details (4)

Auto-updated Aug 3, 2026
Patch available. Sources: github.
github Patch Available

Disabled SSH host key verification in Amazon AWS CLI EMR helper commands · Advisory · aws/aws-cli · GitHub

https://github.com/aws/aws-cli/security/advisories/GHSA-hqvf-45jj-mccq
generic

aws-cli/CHANGELOG.rst at v2 · aws/aws-cli · GitHub

https://github.com/aws/aws-cli/blob/v2/CHANGELOG.rst
generic

aws-cli/CHANGELOG.rst at develop · aws/aws-cli · GitHub

https://github.com/aws/aws-cli/blob/develop/CHANGELOG.rst
generic

CVE-2026-18654 - Disabled SSH host key verification in AWS CLI EMR helper commands

https://aws.amazon.com/security/security-bulletins/2026-071-aws/

Vendor Advisories for CVE-2026-18654(2)

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)
PyPI(1)
PackageVulnerable rangeFixed inDependents
awscli0.10.1 ... 1.9.9 (2458 versions)1.45.28

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 14× in last 7d / 35× 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. 2026-08-19 22:13 UTCEG score recompute
  3. 2026-08-19 17:03 UTCEPSS rescore
  4. 2026-08-18 23:35 UTCEG score recompute
  5. 2026-08-18 13:48 UTCEPSS rescore
  6. 2026-08-18 00:59 UTCEG score recompute
  7. 2026-08-17 13:47 UTCEPSS rescore
  8. 2026-08-17 02:21 UTCEG score recompute
  9. 2026-08-16 14:56 UTCEPSS rescore
  10. 2026-08-16 03:45 UTCEG score recompute
  11. 2026-08-16 02:14 UTCEPSS rescore
  12. 2026-08-15 05:09 UTCEG score recompute
  13. 2026-08-15 01:30 UTCEPSS rescore
  14. 2026-08-14 06:33 UTCEG score recompute
  15. 2026-08-13 22:00 UTCEPSS rescore
  16. 2026-08-13 07:57 UTCEG score recompute
  17. 2026-08-12 13:50 UTCEPSS rescore
  18. 2026-08-12 09:21 UTCEG score recompute
  19. 2026-08-11 13:42 UTCEPSS rescore
  20. 2026-08-11 10:45 UTCEG score recompute
  21. 2026-08-11 00:00 UTCEPSS rescore
  22. 2026-08-10 12:09 UTCEG score recompute
  23. 2026-08-09 13:46 UTCEPSS rescore
  24. 2026-08-09 13:33 UTCEG score recompute
  25. 2026-08-08 16:37 UTCEPSS rescore
Show 10 more
  1. 2026-08-08 14:58 UTCEG score recompute
  2. 2026-08-06 17:46 UTCEG score recompute
  3. 2026-08-06 13:46 UTCEPSS rescore
  4. 2026-08-05 19:17 UTCEPSS rescore
  5. 2026-08-04 20:34 UTCEG score recompute
  6. 2026-08-04 20:07 UTCEG score recompute
  7. 2026-08-04 15:10 UTCEPSS rescore
  8. 2026-08-03 20:19 UTCEG score recompute
  9. 2026-08-03 20:13 UTCEG score recompute
  10. 2026-08-03 20:13 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-18654?
CVE-2026-18654 is a medium vulnerability published on August 3, 2026. Key exchange without entity authentication in the EMR SSH helper commands in Amazon AWS CLI before 1.45.28 and AWS CLI v2 before 2.35.3 might allow man-in-the-middle attackers to intercept SSHsessions and file transfers via network positioning between the client and the EMR cluster endpoint. To…
When was CVE-2026-18654 disclosed?
CVE-2026-18654 was first published in the National Vulnerability Database on August 3, 2026, with the most recent update on August 4, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-18654 actively exploited?
CVE-2026-18654 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 78.3% of all scored CVEs.
What is the CVSS score of CVE-2026-18654?
CVE-2026-18654 has a CVSS v3 base score of 6.8 (NVD).
How do I remediate CVE-2026-18654?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-18654, 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-2026-18654

Explore →

Is Your Infrastructure Affected by CVE-2026-18654?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.