CVE-2021-21668
No exploitation reported by the sources we read.
- Published2021-06-16
- WeaknessCWE-79
Am I affected?
Debian, Ubuntu or Red Hat sometimes backport a fix without changing the upstream version number: such a version reads « to verify », never « affected ».With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.
Description
Jenkins Scriptler Plugin 3.1 and earlier does not escape script content, resulting in a stored cross-site scripting (XSS) vulnerability exploitable by attackers with Scriptler/Configure permission.
Timeline
dates in UTC- 2021-06-1614:15CVE publishedNVD
- 2026-10-2319:23EPSS crossed 10 %FIRST EPSS
Observed activity
isMalicious corpus · updated 2026-10-23 18:48 UTCBlock these indicators
- Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2021-21668?format=txt
- CSV export: https://api.ismalicious.com/edl/cve/CVE-2021-21668?format=csv
- TAXII collection of exploited CVEs
- The EDL and CSV take an API key on the Pro plan.
Versions per branch
NVD| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 3.1 | ≤ 3.1 | no fix published | NVD |
as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.
Fix
Advisories and patches
- www.jenkins.ioVendor Advisory
Detection
- Nuclei template
- none so far ProjectDiscovery
- Exploit-DB
- no entry Exploit-DB
- Proof-of-concept repositories
- none listed PoC-in-GitHub
Sources
- NVDCVSS 3.15.4read 2026-10-23
- NVDCVSS 2.03.5read 2026-10-23
- NVDweakness (CWE)CWE-79read 2026-10-23
- FIRST EPSSEPSS score76.0 %read 2026-10-23
Technical details
- CVSS v3 Vector
- CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
- Published
- 2021-06-16
- Last Modified
- 2026-06-17
- NVD status
- Modified
Frequently asked questions
What is CVE-2021-21668?
Is CVE-2021-21668 actively exploited?
What is the CVSS score for CVE-2021-21668?
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Related vulnerabilities
Same product first, then the same vendor advisory and the same publication week.