CVE-2020-4070

Cross-site Scripting in CSS Validator

Description

In CSS Validator less than or equal to commit 54d68a1, there is a cross-site scripting vulnerability in handling URIs. A user would have to click on a specifically crafted validator link to trigger it. This has been patched in commit e5c09a9.

Category

4.6
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.34%
Vendor Advisory github.com
Affected: World Wide Web Consortium (W3C) CSS Validator
Published at:
Updated at:

References

Link Tags
https://github.com/w3c/css-validator/security/advisories/GHSA-wf36-7w73-rh8c vendor advisory
https://github.com/w3c/css-validator/commit/e5c09a9119167d3064db786d5f00d730b584a53b patch

Frequently Asked Questions

What is the severity of CVE-2020-4070?
CVE-2020-4070 has been scored as a medium severity vulnerability.
How to fix CVE-2020-4070?
To fix CVE-2020-4070, 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-2020-4070 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2020-4070 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2020-4070?
CVE-2020-4070 affects World Wide Web Consortium (W3C) CSS Validator.
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