Skip to main content
Report · AWS Security BulletinsAbout CVE-2026-18654Published Updated

CVE-2026-18654: AWS CLI EMR helper commands · Disabled SSH Host Key Verification

Source AWS Security Bulletins

0
Compare
Authoritative record:CVE-2026-18654· Medium 6.9

Not known to be exploited · CVSS 6.9 Medium · patch available : update aws-cli when convenient.

Data as of 5 Nov 2026, 23:24 UTC

CVSS 4.0 base score
6.9Medium
How severe the flaw is on the 0–10 CVSS scale.
EPSS
0.4% chance of exploitation in 30 days – higher than 40% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch
Available
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:N/SA:N

Exploitation evidence

  1. Disclosed: evidence found.

    CVE published 3 Aug 2026

  2. Detectable: no evidence on record.

    No public nuclei template indexed

  3. Weaponized: no evidence on record.

    No public exploit code indexed in Metasploit or Exploit-DB

  4. Exploited in the wild: no evidence on record.

    Not in CISA KEV and no source reports exploitation

  5. Observed by OffSeq Mirage: no evidence on record.

    No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 5 Nov 2026.

What to do

Affected software

ProductAffectedFixed in
AWSaws-cliAffected
  • <=1.45.27
  • <=2.35.2
Fixed in–

AI-suggested

AWS has released fixed versions of the AWS CLI: v1.45.28 and v2.35.3, which restore proper SSH host key verification. Users must upgrade to these versions or later to remediate the vulnerability. There is no workaround available because the insecure SSH option was hardcoded and cannot be overridden. Users should also ensure any forked or derivative code is updated to incorporate these fixes.

Description

Bulletin ID: 2026-071-AWS Scope: AWS Content Type: Important (requires attention) Publication Date: 08/03/2026 12:30 PM PDT Description: AWS Command Line Interface (AWS CLI) is a unified tool to manage AWS services from the command line. We identified CVE-2026-18654, an issue where the EMR SSH helper commands (aws emr ssh, aws emr socks, aws emr put, aws emr get) disabled SSH host key verification, which might allow man-in-the-middle actors to intercept SSH sessions and file transfers via network positioning between the client and the EMR cluster endpoint. Impacted versions: - AWS CLI v1 <= 1.45.27 - AWS CLI v2 <= 2.35.2 Please refer to the article below for the most up-to-date and complete information related to this AWS Security Bulletin.

References

Community reviews

Loading reviews…