CVE-2023-49288

Denial of Service in HTTP Collapsed Forwarding in Squid

Description

Squid is a caching proxy for the Web supporting HTTP, HTTPS, FTP, and more. Affected versions of squid are subject to a a Use-After-Free bug which can lead to a Denial of Service attack via collapsed forwarding. All versions of Squid from 3.5 up to and including 5.9 configured with "collapsed_forwarding on" are vulnerable. Configurations with "collapsed_forwarding off" or without a "collapsed_forwarding" directive are not vulnerable. This bug is fixed by Squid version 6.0.1. Users are advised to upgrade. Users unable to upgrade should remove all collapsed_forwarding lines from their squid.conf.

Category

8.6
CVSS
Severity: High
CVSS 3.1 •
EPSS 1.86% Top 20%
Vendor Advisory github.com
Affected: squid-cache squid
Published at:
Updated at:

References

Link Tags
https://github.com/squid-cache/squid/security/advisories/GHSA-rj5h-46j6-q2g5 vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/MEV66D3PAAY6K7TWDT3WZBLCPLASFJDC/
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/A5QASTMCUSUEW3UOMKHZJB3FTONWSRXS/
https://security.netapp.com/advisory/ntap-20240119-0006/

Frequently Asked Questions

What is the severity of CVE-2023-49288?
CVE-2023-49288 has been scored as a high severity vulnerability.
How to fix CVE-2023-49288?
To fix CVE-2023-49288, 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-2023-49288 being actively exploited in the wild?
It is possible that CVE-2023-49288 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~2% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2023-49288?
CVE-2023-49288 affects squid-cache squid.
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