CVE-2019-18676 Memory corruption in n/a

What is CVE-2019-18676?

CVE-2019-18676 is a high-severity memory corruption vulnerability in Canonical Ubuntu Linux, published on 26 Nov 2019. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

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.

Weakness: CWE-787

Which versions are affected by CVE-2019-18676?

It affects 4 products.

Products include Canonical Ubuntu Linux, Debian Debian Linux, Fedoraproject Fedora, Squid-Cache Squid.

How do I fix CVE-2019-18676?

Upgrade to a fixed version.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2019-18676 being exploited?

There is no known exploitation of CVE-2019-18676 in the wild and no public exploit code.

Other vulnerabilities in Canonical Ubuntu Linux

• CVE-2020-11651 SaltStack Salt Authentication Bypass Exploited Critical 9.8
• CVE-2020-7247 OpenSMTPD Remote Code Execution Exploited Critical 9.8
• CVE-2019-16928 Exim Out-of-bounds Write Exploited Critical 9.8
• CVE-2018-6789 Exim Buffer Overflow Exploited Critical 9.8
• CVE-2015-2590 Oracle Java SE and Java SE Embedded Remote Code Execution Exploited Critical 9.8

All Canonical Ubuntu Linux vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as DEBIAN-CVE-2019-18676, GHSA-chw7-jm99-chw8, UBUNTU-CVE-2019-18676.