CVE-2021-31930 json
Persistent cross-site scripting (XSS) in the web interface of Concerto through 2.3.6 allows an unauthenticated remote attacker to introduce…
published 2021-05-19 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-18803
- cvss
- 6.1
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.9%
- EPSS 0.9% chance of exploitation in 30 days, percentile 60%
- public exploits
- 0
- none known
Summary
Persistent cross-site scripting (XSS) in the web interface of Concerto through 2.3.6 allows an unauthenticated remote attacker to introduce arbitrary JavaScript by injecting an XSS payload into the First Name or Last Name parameter upon registration. When a privileged user attempts to delete the account, the XSS payload will be executed.
Patch / fix
- github.com/concerto/concerto#1558 pull request
Exploit prediction
0.92% chance of exploitation in the next 30 days, higher than 60% of all scored CVEs (FIRST EPSS, 2026-11-08).
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
/concerto/concerto/pull/1558
third-party-advisory
-
github.com
/concerto/concerto/security/advisories
third-party-advisory
Sources
- CVE List CVE-2021-31930
- NVD CVE-2021-31930
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