CVE-2021-21621

mediumpriority · track · 21EPSS 0.012 · 68 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

1.21% (68th) EPSS

CVSS 5 · medium

Is it mine?

3 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · nvd · osv

EPSS · scored 2026-10-23

Jenkins Support Core Plugin 2.72 and earlier provides the serialized user authentication as part of the "About user (basic authentication details only)" information, which can include the session ID of the user creating the support bundle in some configurations.

cvss

Technical severity, 0–10. One row per scoring source.

5.3

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–medium · 3.1–5.3

v2.05mediumAV:N/AC:L/Au:N/C:P/I:N/A:Nprimary · NVD / NIST USexploitability 10 · impact 2.9

v3.15.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:Nprimary · NVD / NIST USexploitability 3.9 · impact 1.4

v3.13.1lowCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:Nsecondary · OSV

v3.14.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-200USprimaryCWE-200US

affected products (3)

Products and version ranges known to be affected.

Jenkins Project Jenkins Support Core Plugin≤ unspecified ≤2.72enisa_euvdEU
jenkins support core≤ 2.72nvdUScpe:2.3:a:jenkins:support_core:*:*:*:*:*:*:*:*
Maven org.jenkins-ci.plugins:support-core< 2.72.1osvUSpkg:maven/org.jenkins-ci.plugins/support-core

advisories (1)

Vendor and ecosystem advisories describing this.

GHSA-92pg-8g57-hqpxSupport bundles can include user session IDs in Jenkins Support Core Plugin2022-05-24ghsa · osvUS
Support Core Plugin 2.72 and earlier provides the serialized user authentication as part of the \"About user (basic authentication details only)\" information (`user.md`). In some configurations, this can include the session ID of the user creating the support bundle. Attackers with access to support bundle content and the Jenkins instance could use this information to impersonate the user who created the support bundle. Support Core Plugin 2.72.1 no longer provides the serialized user authentication as part of the \"About user (basic authentication details only)\" information. As a workaround, deselecting \"About user (basic authentication details only)\" before creating a support bundle will exclude the affected information from the bundle.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd osv NVD CVE.org MITRE

published 2021-02-24modified 2026-06-17

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references (5)

External citations — patches, advisories, analysis.

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