CVE-2020-26239

Cross-Site Scripting in Scratch browser addons

Description

Scratch Addons is a WebExtension that supports both Chrome and Firefox. Scratch Addons before version 1.3.2 is vulnerable to DOM-based XSS. If the victim visited a specific website, the More Links addon of the Scratch Addons extension used incorrect regular expression which caused the HTML-escaped values to be unescaped, leading to XSS. Scratch Addons version 1.3.2 fixes the bug. The extension will be automatically updated by the browser. More Links addon can be disabled via the option of the extension.

Category

7.6
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.28%
Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com
Affected: ScratchAddons ScratchAddons
Published at:
Updated at:

References

Link Tags
https://github.com/ScratchAddons/ScratchAddons/security/advisories/GHSA-6qfq-px3r-xj4p third party advisory patch
https://github.com/ScratchAddons/ScratchAddons/commit/b9a52d6532c8514254c7cc1d8e18710dbedc41ff third party advisory patch
https://github.com/ScratchAddons/ScratchAddons/blob/a471893df403f86c9182970678175d4772a0690c/addons/more-links/userscript.js#L15 third party advisory
https://github.com/ScratchAddons/ScratchAddons/releases/tag/v1.3.2 third party advisory release notes

Frequently Asked Questions

What is the severity of CVE-2020-26239?
CVE-2020-26239 has been scored as a high severity vulnerability.
How to fix CVE-2020-26239?
To fix CVE-2020-26239, 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-2020-26239 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2020-26239 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-2020-26239?
CVE-2020-26239 affects ScratchAddons ScratchAddons.
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