CVE-2019-18676: Buffer Overflow

Published Nov 26, 2019
·
Updated

An issue was discovered in Squid 3.x and 4.x through 4.8. Due to incorrect input validation, there is a heap-based buffer overflow that can result in Denial of Service to all clients using the proxy. Severity is high due to this vulnerability occurring before normal security checks; any remote client that can reach the proxy port can trivially perform the attack via a crafted URI scheme.

Affected Software

12 affected componentsFixes available
Squid-Cache Squid>=3.0<=3.5.28
Squid-Cache Squid>=4.0<=4.8
Canonical Ubuntu Linux=16.04
Canonical Ubuntu Linux=18.04
Canonical Ubuntu Linux=19.04
Canonical Ubuntu Linux=19.10
Fedoraproject Fedora=30
Fedoraproject Fedora=31
Debian Debian Linux=9.0
Debian Debian Linux=10.0
Canonical Ubuntu Linux=16.04
debian/squid
4.13-10+deb11u34.13-10+deb11u65.7-2+deb12u55.7-2+deb12u46.13-2+deb13u17.4-1

Event History

Nov 26, 2019
CVE Published
via MITRE·04:23 PM
Data Sourced
via MITRE·04:23 PM
Description
Feb 20, 2026
Data Sourced
via Ubuntu·10:42 PM
RemedyDescriptionSeverityAffected Software
Data Sourced
via Launchpad·10:43 PM
Description
Data Sourced
via Debian·10:43 PM
DescriptionAffected Software

Frequently Asked Questions

1

What is CVE-2019-18676?

CVE-2019-18676 is an issue discovered in Squid 3.x and 4.x through 4.8, which results in a heap-based buffer overflow that can lead to Denial of Service attacks.

2

How severe is CVE-2019-18676?

CVE-2019-18676 has a severity rating of 7.5 (high).

3

How does CVE-2019-18676 impact Squid users?

CVE-2019-18676 can cause Denial of Service for all clients using the Squid proxy.

4

Which versions of Squid are affected by CVE-2019-18676?

Squid versions 3.x and 4.x through 4.8 are affected by CVE-2019-18676.

5

Where can I find more information about CVE-2019-18676?

You can find more information about CVE-2019-18676 in the Squid advisory and patches, as well as the Bugzilla entry.

Contact

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