CVE-2021-25318Network attack vector

Unauthorized resource modification via wildcard API groups

Published Jul 15, 2021 · Updated Sep 16, 2024

Incorrect RBAC permissions in Rancher 2.0.0 through 2.4.15 and 2.5.0 through 2.5.8 allow remote authenticated users to modify protected resources. Rancher creates Kubernetes RBAC rules without the intended API-group restriction, turning access to a named resource in one group into access across matching resource names in other groups. Any cluster user holding the affected grant can reach management or downstream-cluster objects outside the intended authorization boundary, including secrets and cluster-level resources.

CVSS severity8.8
High
EPSS probability1.05%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Incorrect RBAC permissions in Rancher 2.0.0 through 2.4.15 and 2.5.0 through 2.5.8 allow remote authenticated users to modify protected resources. Rancher creates Kubernetes RBAC rules without the intended API-group restriction, turning access to a named resource in one group into access across matching resource names in other groups. Any cluster user holding the affected grant can reach management or downstream-cluster objects outside the intended authorization boundary, including secrets and cluster-level resources.

The record

CVE
CVE-2021-25318
Published
Jul 15, 2021
Updated
Sep 16, 2024
Vendor
Rancher
Product
Rancher
Classifications
CWE-732, T1548
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jul 15, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=Rancher <2.4.16
  2. Affected versionversion=Rancher <2.5.9

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Rancher · Rancherversion=Rancher <2.4.16; version=Rancher <2.5.9

Published CVSS scores

8.8SUSECVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
8.7GitHubCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
6.5NVDAV:N/AC:L/Au:S/C:P/I:P/A:P
8.8NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-732Incorrect Permission Assignment for Critical Resource
T1548Abuse Elevation Control Mechanism

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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