CVE-2021-25320 | Rancher: Cloud credentials can be used through proxy API by users without access

A Improper Access Control vulnerability in Rancher, allows users in the cluster to make request to cloud providers by creating requests with the cloud-credential ID. Rancher in this case would attach the requested credentials without further checks This issue affects: Rancher versions prior to 2.5.9; Rancher versions prior to 2.4.16.

Published: 2021-07-15 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-25320 is rated Moderate Risk (58.7/100): CVSS Critical severity, with medium exploitation likelihood (EPSS 0.83%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-25320

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.20% 0.83% +0.63%
2 2025-10-26 0.26% 0.20% -0.06%
3 2025-03-30 — 0.26% —

Full EPSS history (10 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-25320

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.9 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.1 6.0 [email protected]
9.9 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.1 6.0 [email protected]
4.0 2.0 MEDIUM
AV:N/AC:L/Au:S/C:P/I:N/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:S)
A single authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:N)
No availability impact.
 8.0 2.9 [email protected]

Weakness enumeration for CVE-2021-25320

GitHub Security Advisory for CVE-2021-25320

GHSA-gqf8-rvrh-g7w6 · Severity: critical · Ecosystem: go — Rancher cloud credentials can be used through proxy API by users without access

OS Trackers for CVE-2021-25320

vendor priority summary link
suse critical — https://www.suse.com/security/cve/CVE-2021-25320/

Affected software / configurations for CVE-2021-25320

Vendor Product Version Raw CPE
rancher rancher < 2.4.16 cpe:2.3:a:rancher:rancher:*:*:*:*:*:*:*:*
rancher rancher >= 2.5.0, < 2.5.9 cpe:2.3:a:rancher:rancher:*:*:*:*:*:*:*:*

References for CVE-2021-25320

URL Tags
https://bugzilla.suse.com/show_bug.cgi?id=1185514 Issue Tracking Third Party Advisory
cvelogic Threat Intelligence