CVE-2021-41819

Public Exploit

Description

CGI::Cookie.parse in Ruby through 2.6.8 mishandles security prefixes in cookie names. This also affects the CGI gem through 0.3.0 for Ruby.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.47%
Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org Vendor Advisory gentoo.org Vendor Advisory ruby-lang.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://hackerone.com/reports/910552 third party advisory permissions required
https://www.ruby-lang.org/en/news/2021/11/24/cookie-prefix-spoofing-in-cgi-cookie-parse-cve-2021-41819/ exploit vendor advisory
https://security.netapp.com/advisory/ntap-20220121-0003/ third party advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/IUXQCH6FRKANCVZO2Q7D2SQX33FP3KWN/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UTOJGS5IEFDK3UOO7IY4OTTFGHGLSWZF/ vendor advisory
https://security.gentoo.org/glsa/202401-27 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-41819?
CVE-2021-41819 has been scored as a high severity vulnerability.
How to fix CVE-2021-41819?
To fix CVE-2021-41819, 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-2021-41819 being actively exploited in the wild?
It is possible that CVE-2021-41819 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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