How severe is CVE-2021-21670?

CVE-2021-21670 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2021-21670 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-21670?

CVE-2021-21670 primarily affects Jenkins. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-21670?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-21670 published?

CVE-2021-21670 was published on 2021-06-30 and last updated on 2026-06-17.

CVE-2021-21670

CVE-2021-21670 is a medium-severity vulnerability in Jenkins with a CVSS 3.x base score of 4.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Medium (CVSS 3.x base score 4.3)
CVSS v2: 4.0
EPSS exploit prediction: 2% (78th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Jenkins
Published: 2021-06-30
Last modified: 2026-06-17

Description

Jenkins 2.299 and earlier, LTS 2.289.1 and earlier allows users to cancel queue items and abort builds of jobs for which they have Item/Cancel permission even when they do not have Item/Read permission.

Frequently asked questions

What is CVE-2021-21670?: Jenkins 2.299 and earlier, LTS 2.289.1 and earlier allows users to cancel queue items and abort builds of jobs for which they have Item/Cancel permission even when they do not have Item/Read permission.
How severe is CVE-2021-21670?: CVE-2021-21670 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2021-21670 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-21670?: CVE-2021-21670 primarily affects Jenkins. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-21670?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-21670 published?: CVE-2021-21670 was published on 2021-06-30 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:jenkins:jenkins:*:*:*:*:lts:*:*:*
cpe:2.3:a:jenkins:jenkins:*:*:*:*:-:*:*:*

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