CVE-2021-21687: jenkins project jenkins Missing Authorization
Vulnerability summary
CVE-2021-21687 is a critical (CVSS 9.1) Missing Authorization vulnerability in jenkins project jenkins. EPSS estimates a 1.43% chance of exploitation in the next 30 days, higher than 72.9% of scored vulnerabilities.
Severe, CVSS 9.1 (NVD); no exploitation reported by the 5 checked sources; EPSS 1% (FIRST, 03-11-2026)
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 6Timeline
- 04-11-2021PublishedVulnerability first disclosed.
- 03-08-2024Last modifiedVulnerability information updated.
Description
Jenkins 2.318 and earlier, LTS 2.303.2 and earlier does not check agent-to-controller access to create symbolic links when unarchiving a symbolic link in FilePath#untar.
CVSS metrics
3 scores · 2 sources · 2 versions- OSV · MavenEcosystem advisory · calculated9.0CriticalCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:HDiffers
EPSS trend
Probability
1.43%
Chance of exploitation in the next 30 days
Percentile
73%
Versus all other CVEs
30-day change
No change 0.00 pp
From 1.43% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.
Jenkins1 product
- jenkins< 2.303.3 | < 2.319
Jenkins project1 product
- jenkins≥ unspecified, ≤ 2.318 | ≥ unspecified, ≤ LTS 2.303.2
Org.jenkins-ci.main1 product
- jenkins-core< 2.303.3 | ≥ 2.304, < 2.319
3 vendors · 3 products
References
3 links
- github.com/jenkinsci/jenkinsPACKAGE