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CVE-2025-23390

Fleet doesn’t validate a server’s certificate when connecting through SSH

No known exploitation. EPSS puts it in the 8th percentile. Fixed versions are out.

CVSS 3.16.3MediumEPSS percentile8th0.2% chance in 30 daysCISA KEVNot listedNo confirmed exploitation
No public exploit knownFix2 products3 fixed builds listed below

Published Updated Sources: CVE.org, NVD, GitHub

NVD CVE.org

What to do

Find your product and version, then upgrade to the build on the right.

  • SUSE fleetAffected: ≥ 0.9.0-rc.1, < 0.10.12Upgrade to: 0.10.12Affected: ≥ 0.11.0, < 0.11.7Upgrade to: 0.11.7Affected: ≥ 0.12.0, < 0.12.2Upgrade to: 0.12.2Stated by: CVE record
  • Go github.com/rancher/fleetAffected: ≥ 0.9.0-rc.1, < 0.10.12Upgrade to: 0.10.12Stated by: GitHub advisory

Versions as the sources state them. Full version matrix after sign-in

Check it yourselfA free OpenVAS check exists for this CVE. Run it against your hosts.Is your organisation exposed?Request an assessment to establish which checks fit your systems.

What it is

From the CVE record

A vulnerability has been identified within Fleet where, by default, Fleet will automatically trust a remote server’s certificate when connecting through SSH if the certificate isn’t set in the `known_hosts` file. This could allow the execution of a man-in-the-middle (MitM) attack against Fleet. In case the server that is being connected to has a trusted entry in the known_hosts file, then Fleet will correctly check the authenticity of the presented certificate.

In plain language

No plain-language summary for this CVE yet.

Exploitation

Where each signal puts this CVE on the scale from published to confirmed exploited.

EPSS8th
CISA KEV

Not in the catalog. CISA has not confirmed exploitation.

Public exploits

No public exploit or proof of concept found in the sources we track.

EPSS

0.2% chance of exploitation activity in the next 30 days, which ranks it in the 8th percentile of scored CVEs.

Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.

Lifecycle

17 events over 542 days, from the signal feeds we watch.

  1. Patch availablerecord updated
  2. Patch availablerecord updated
  3. Patch availablepatch available, published, weakness classified, att&ck mapped, record updated, record updated
  4. OpenVAS check added
  5. Patch availablerecord updated
  6. Publishedweakness classified, att&ck mapped

Affected products

Technical detail

CVSS 3.1 vector

Open in the CVSS calculator

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L

Scored 6.3 by NVD.

How it is reached

  • Attack Vector NetworkExploitable remotely over the network without any special conditions
  • Attack Complexity LowNo special conditions — the attack can be reliably reproduced
  • Privileges Required LowRequires basic user-level privileges
  • User Interaction NoneNo user interaction needed — fully automated exploitation

Scope

  • Scope UnchangedImpact is limited to the vulnerable component itself

Impact if exploited

  • Confidentiality LowSome restricted information is disclosed, but limited in scope
  • Integrity LowData modification is possible but limited in scope or consequence
  • Availability LowReduced performance or intermittent disruption of service

Weaknesses

ATT&CK techniques

Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.

Sources

References in the record

And 7 more references. See all after sign-in

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We'll flag the next CVE, public exploit or patch for Fleet, not every advisory.