CVE-2021-31806

Description

An issue was discovered in Squid before 4.15 and 5.x before 5.0.6. Due to a memory-management bug, it is vulnerable to a Denial of Service attack (against all clients using the proxy) via HTTP Range request processing.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 81.19% Top 5%
Vendor Advisory debian.org Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org Vendor Advisory squid-cache.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://github.com/squid-cache/squid/security/advisories/GHSA-pxwq-f3qr-w2xf third party advisory patch
http://www.squid-cache.org/Versions/v4/changesets/squid-4-e7cf864f938f24eea8af0692c04d16790983c823.patch patch vendor advisory
https://www.debian.org/security/2021/dsa-4924 third party advisory vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LSQ3U54ZCNXR44QRPW3AV2VCS6K3TKCF/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/T4EPIWUZDJAXADDHVOPKRBTQHPBR6H66/ vendor advisory
https://lists.debian.org/debian-lts-announce/2021/06/msg00014.html third party advisory mailing list
https://security.netapp.com/advisory/ntap-20210716-0007/ third party advisory
http://www.openwall.com/lists/oss-security/2023/10/11/3 third party advisory mailing list
http://seclists.org/fulldisclosure/2023/Oct/14 third party advisory mailing list

Frequently Asked Questions

What is the severity of CVE-2021-31806?
CVE-2021-31806 has been scored as a medium severity vulnerability.
How to fix CVE-2021-31806?
To fix CVE-2021-31806, 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-2021-31806 being actively exploited in the wild?
It is possible that CVE-2021-31806 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~81% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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