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Fencer Intel
high 8.8

CVE-2026-88808 json

Fleet agent copies downstream resources with cluster-admin privileges, allowing cross-namespace writes on downstream clusters

published last mo. modified last mo. also EUVD-2026-88335 , GHSA-q9v4-358v-r8q5

Unreviewed: the maintainers' own advisory

Published by the maintainers on their GitHub repository rancher/fleet. GitHub has not reviewed it into the GitHub Advisory Database, so the affected packages and versions are the maintainers' word. Read the full advisory on GitHub.

cvss
8.8
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.3%
EPSS 0.3% chance of exploitation in 30 days, percentile 20%
public exploits
0
none known

Summary

A vulnerability has been identified within Rancher Manager where the Fleet agent wrote resources to downstream clusters using its own cluster-admin credentials instead of the ServiceAccount pinned to the deployment. It affects multi-tenancy environments where different tenants share the same downstream clusters, for example different privileged or untrusted teams inside the same organization. This could lead to overwritten configuration files.

This issue affected SUSE Rancher Fleet 0.16 before 0.16.2, 0.15 before 0.15.7, and 0.14 before 0.14.11.

Patch / fix

  • SUSE Rancher 0.14.11, 0.15.7, 0.16.2

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CISA SSVC

Exploitation
none
Automatable
no
Technical impact
total
Assessed
last mo.

Exploit prediction

0.28% chance of exploitation in the next 30 days, higher than 20% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by version score vector
CNA 3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected products

  • SUSE Rancher

Classification

Weakness
  • CWE-250 Execution with Unnecessary Privileges

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

The maintainers of rancher/fleet published their own advisory on GitHub. Reviewed sources take precedence over it.