How severe is CVE-2021-21690?

CVE-2021-21690 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-21690 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (82nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-21690?

CVE-2021-21690 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-2021-21690?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2021-21690 published?

CVE-2021-21690 was published on 2021-11-04 and last updated on 2026-06-17.

CVE-2021-21690

CVE-2021-21690 is a critical-severity vulnerability in Jenkins with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-22.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 2% (82nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-22
Affected product: Jenkins
Published: 2021-11-04
Last modified: 2026-06-17

Description

Agent processes are able to completely bypass file path filtering by wrapping the file operation in an agent file path in Jenkins 2.318 and earlier, LTS 2.303.2 and earlier.

Frequently asked questions

What is CVE-2021-21690?: Agent processes are able to completely bypass file path filtering by wrapping the file operation in an agent file path in Jenkins 2.318 and earlier, LTS 2.303.2 and earlier.
How severe is CVE-2021-21690?: CVE-2021-21690 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-21690 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (82nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-21690?: CVE-2021-21690 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-2021-21690?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-21690 published?: CVE-2021-21690 was published on 2021-11-04 and last updated on 2026-06-17.

References

https://www.jenkins.io/security/advisory/2021-11-04/#SECURITY-2455

Affected products (2)

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

More vulnerabilities in Jenkins

CVE-2024-23897 — Critical (CVSS 9.8): Jenkins 2.441 and earlier, LTS 2.426.2 and earlier does not disable a feature of its CLI command parser that replaces…
CVE-2021-21696 — Critical (CVSS 9.8): Jenkins 2.318 and earlier, LTS 2.303.2 and earlier does not limit agent read/write access to the libs/ directory inside…
CVE-2021-21694 — Critical (CVSS 9.8): FilePath#toURI, FilePath#hasSymlink, FilePath#absolutize, FilePath#isDescendant, and FilePath#get*DiskSpace do not…
CVE-2021-21693 — Critical (CVSS 9.8): When creating temporary files, agent-to-controller access to create those files is only checked after they've been…
CVE-2021-21692 — Critical (CVSS 9.8): FilePath#renameTo and FilePath#moveAllChildrenTo in Jenkins 2.318 and earlier, LTS 2.303.2 and earlier only check…
CVE-2021-21691 — Critical (CVSS 9.8): Creating symbolic links is possible without the 'symlink' agent-to-controller access control permission in Jenkins…

All CVEs affecting Jenkins →

Other CWE-22 (Path Traversal) vulnerabilities

CVE-2026-48282 — Critical (CVSS 10.0): ColdFusion versions 2025.9, 2023.20 and earlier are affected by an Improper Limitation of a Pathname to a Restricted…
CVE-2026-54917 — Critical (CVSS 10.0): SeaweedFS is a distributed storage system for object storage (S3), file systems, and Iceberg tables. Prior to 4.30, the…
CVE-2026-11429 — Critical (CVSS 10.0): Two endpoints in the Vault Service ScriptsController, shared by Altium Enterprise Server and Altium 365, accept file…
CVE-2026-34909 — Critical (CVSS 10.0): A malicious actor with access to the network could exploit a Path Traversal vulnerability found in UniFi OS devices to…
CVE-2026-7411 — Critical (CVSS 10.0): In Eclipse BaSyx Java Server SDK versions prior to 2.0.0-milestone-10, inadequate path normalization in the Submodel…
CVE-2026-36767 — Critical (CVSS 10.0): A path traversal vulnerability in the /content/images/add endpoint of shopizer v3.2.5 allows attackers write arbitrary…

Browse all CWE-22 (Path Traversal) vulnerabilities →