CVE-2018-1000027

Description

The Squid Software Foundation Squid HTTP Caching Proxy version prior to version 4.0.23 contains a NULL Pointer Dereference vulnerability in HTTP Response X-Forwarded-For header processing that can result in Denial of Service to all clients of the proxy. This attack appear to be exploitable via Remote HTTP server responding with an X-Forwarded-For header to certain types of HTTP request. This vulnerability appears to have been fixed in 4.0.23 and later.

Category

7.5
CVSS
Severity: High
CVSS 3.0 •
CVSS 2.0 •
EPSS 78.24% Top 5%
Vendor Advisory ubuntu.com Vendor Advisory debian.org Vendor Advisory ubuntu.com Vendor Advisory squid-cache.org Vendor Advisory squid-cache.org Vendor Advisory squid-cache.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://usn.ubuntu.com/3557-1/ third party advisory vendor advisory
http://www.squid-cache.org/Versions/v4/changesets/SQUID-2018_2.patch patch vendor advisory
https://www.debian.org/security/2018/dsa-4122 third party advisory vendor advisory
http://www.squid-cache.org/Advisories/SQUID-2018_2.txt patch vendor advisory
https://lists.debian.org/debian-lts-announce/2018/02/msg00001.html third party advisory mailing list
https://github.com/squid-cache/squid/pull/129/files third party advisory
http://www.squid-cache.org/Versions/v3/3.5/changesets/SQUID-2018_2.patch patch vendor advisory
https://lists.debian.org/debian-lts-announce/2018/02/msg00002.html third party advisory mailing list
https://usn.ubuntu.com/4059-2/ vendor advisory

Frequently Asked Questions

What is the severity of CVE-2018-1000027?
CVE-2018-1000027 has been scored as a high severity vulnerability.
How to fix CVE-2018-1000027?
To fix CVE-2018-1000027, 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-2018-1000027 being actively exploited in the wild?
It is possible that CVE-2018-1000027 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~78% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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