CVE-2020-6817

Public Exploit

Description

bleach.clean behavior parsing style attributes could result in a regular expression denial of service (ReDoS). Calls to bleach.clean with an allowed tag with an allowed style attribute are vulnerable to ReDoS. For example, bleach.clean(..., attributes={'a': ['style']}).

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
EPSS 0.17%
Vendor Advisory github.com
Affected: Mozilla Mozilla Bleach
Published at:
Updated at:

References

Link Tags
https://github.com/mozilla/bleach/security/advisories/GHSA-vqhp-cxgc-6wmm vendor advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1623633 issue tracking exploit

Frequently Asked Questions

What is the severity of CVE-2020-6817?
CVE-2020-6817 has been scored as a high severity vulnerability.
How to fix CVE-2020-6817?
To fix CVE-2020-6817, 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-2020-6817 being actively exploited in the wild?
It is possible that CVE-2020-6817 is being exploited or will be exploited in a near future based on public information. 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-2020-6817?
CVE-2020-6817 affects Mozilla Mozilla Bleach.
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