CVE-2021-35955

Description

Contao >=4.0.0 allows backend XSS via HTML attributes to an HTML field. Fixed in 4.4.56, 4.9.18, 4.11.7.

Category

4.8
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.52%
Vendor Advisory contao.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://contao.org/en/news/contao-4-9-16-and-4-11-5-are-available.html vendor advisory
https://github.com/contao/contao/security/advisories/GHSA-hr3h-x6gq-rqcp third party advisory

Frequently Asked Questions

What is the severity of CVE-2021-35955?
CVE-2021-35955 has been scored as a medium severity vulnerability.
How to fix CVE-2021-35955?
To fix CVE-2021-35955, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-35955 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-35955 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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