CVE-2021-21661Network attack vector

Credential ID enumeration via missing permission checks

Published Jun 10, 2021 · Updated Aug 3, 2024

Missing authorization in Jenkins Kubernetes CLI Plugin 1.10.0 and earlier allows remote authenticated users to enumerate credential IDs. Several plugin HTTP endpoints omit permission checks before returning credential identifiers. Overall/Read permission is required, and the exposure discloses identifiers that can support later credential-capture attacks but does not itself alter data.

CVSS severity4.3
Medium
EPSS probability1.64%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Missing authorization in Jenkins Kubernetes CLI Plugin 1.10.0 and earlier allows remote authenticated users to enumerate credential IDs. Several plugin HTTP endpoints omit permission checks before returning credential identifiers. Overall/Read permission is required, and the exposure discloses identifiers that can support later credential-capture attacks but does not itself alter data.

The record

CVE
CVE-2021-21661
Published
Jun 10, 2021
Updated
Aug 3, 2024
Vendor
Jenkins Project
Product
Kubernetes CLI
Classifications
CWE-862, T1087
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 10, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 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=unspecified <=1.10.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Jenkins Project · Kubernetes CLIversion=unspecified <=1.10.0

Published CVSS scores

4.3NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
4.0NVDAV:N/AC:L/Au:S/C:P/I:N/A:N

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-862Missing Authorization
T1087Account Discovery

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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