CVE-2021-27902 json
Craft CMS Cross-site Scripting Vulnerability
published 5y ago modified 4mo ago also GHSA-3jxh-789f-p7m6 , EUVD-2021-1437
- cvss
- 6.1
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.0%
- EPSS 1.0% chance of exploitation in 30 days, percentile 62%
- public exploits
- 0
- none known
Summary
An issue was discovered in Craft CMS before 3.6.0. In some circumstances, a potential XSS vulnerability existed in connection with front-end forms that accepted user uploads.
Patch / fix
Is CVE-2021-27902 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerExploit prediction
0.99% chance of exploitation in the next 30 days, higher than 62% of all scored CVEs (FIRST EPSS, 2026-11-09).
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 |
| GitHub | 3.1 | 6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| packagist | craftcms/cms | <3.6.0 |
3.6.0 |
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
-
github.com
/craftcms/cms/commit/8ee85a8f03c143fa2420e7d6f311d95cae3b19ce
web, patch, third-party-advisory
-
github.com
/craftcms/cms/blob/develop/CHANGELOG.md#security-1
web, release-notes, third-party-advisory
-
github.com
/craftcms/cms/blob/develop/CHANGELOG.md#360---2021-01-26
web, release-notes, third-party-advisory
-
nvd.nist.gov
/vuln/detail/CVE-2021-27902
advisory
Sources
- CVE List CVE-2021-27902
- GitHub Advisory GHSA-3jxh-789f-p7m6
- NVD CVE-2021-27902
Fencer Intel 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.