CVE-2021-27309 json
Clansphere CMS 2011.4 allows unauthenticated reflected XSS via "module" parameter.
published 2021-03-23 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-14070
- cvss
- 6.1
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 2.0%
- EPSS 2.0% chance of exploitation in 30 days, percentile 80%
- public exploits
- 0
- none known, plus a Nuclei check
Summary
Clansphere CMS 2011.4 allows unauthenticated reflected XSS via "module" parameter.
Exploit prediction
1.97% chance of exploitation in the next 30 days, higher than 80% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- Nuclei template Clansphere CMS 2011.4 - Cross-Site Scripting nuclei detection template
- github.com https://github.com/xoffense/POC/blob/main/Clansphere%202011.4%20%22module%22%20xss.md referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
| NVD | 2.0 | 4.3 | AV:N/AC:M/Au:N/C:N/I:P/A:N |
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
-
github.com
/xoffense/POC/blob/main/Clansphere%202011.4%20%22module%22%20xss.md
exploit, third-party-advisory
Sources
- CVE List CVE-2021-27309
- NVD CVE-2021-27309
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.