CVE-2021-36773

Public Exploit

Description

uBlock Origin before 1.36.2 and nMatrix before 4.4.9 support an arbitrary depth of parameter nesting for strict blocking, which allows crafted web sites to cause a denial of service (unbounded recursion that can trigger memory consumption and a loss of all blocking functionality).

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.26%
Third-Party Advisory github.com Third-Party Advisory debian.org Third-Party Advisory ycombinator.com
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://news.ycombinator.com/item?id=27833752 issue tracking third party advisory
https://github.com/vtriolet/writings/blob/main/posts/2021/ublock_origin_and_umatrix_denial_of_service.adoc third party advisory exploit
https://lists.debian.org/debian-lts-announce/2022/06/msg00024.html third party advisory mailing list

Frequently Asked Questions

What is the severity of CVE-2021-36773?
CVE-2021-36773 has been scored as a high severity vulnerability.
How to fix CVE-2021-36773?
To fix CVE-2021-36773, 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-2021-36773 being actively exploited in the wild?
It is possible that CVE-2021-36773 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.
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