CVE-2021-27911 json
XSS vulnerability on contacts view
published 2021-08-30 5 y ago modified 2026-07-08 4 mo ago also GHSA-72hm-fx78-xwhc , EUVD-2021-1999
- cvss
- 8.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.6%
- EPSS 0.6% chance of exploitation in 30 days, percentile 51%
- public exploits
- 0
- none known
Summary
Mautic versions before 3.3.4/4.0.0 are vulnerable to an inline JS XSS attack through the contact's first or last name and triggered when viewing a contact's details page then clicking on the action drop down and hovering over the Campaigns button. Contact first and last name can be populated from different sources such as UI, API, 3rd party syncing, forms, etc.
Patch / fix
- packagist mautic/core 3.3.4, 4.0.0
- Mautic Mautic 3.3.4, 4.0.0
Exploit prediction
0.64% chance of exploitation in the next 30 days, higher than 51% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 8.3 | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:H |
| 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 | 8.3 | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| packagist | mautic/core | <3.3.4 >=4.0.0-alpha1, <4.0.0 |
3.3.4 4.0.0 |
Affected products
- Mautic Mautic
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
-
github.com
/mautic/mautic/security/advisories/GHSA-72hm-fx78-xwhc
web, patch, third-party-advisory
-
nvd.nist.gov
/vuln/detail/CVE-2021-27911
advisory
-
github.com
/FriendsOfPHP/security-advisories/blob/master/mautic/core/CVE-2021-27911.yaml
web
-
github.com
/mautic/mautic
package
Sources
- CVE List CVE-2021-27911
- GitHub Advisory GHSA-72hm-fx78-xwhc
- NVD CVE-2021-27911
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