CVE-2015-8806 Denial of service or RCE from libxml2 and libxslt

What is CVE-2015-8806?

CVE-2015-8806 is a high-severity denial of service vulnerability in Canonical Ubuntu Linux, published on 13 Apr 2016. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

dict.c in libxml2 allows remote attackers to cause a denial of service (heap-based buffer over-read and application crash) via an unexpected character immediately after the "<!DOCTYPE html" substring in a crafted HTML document.

Which versions are affected by CVE-2015-8806?

2 open source packages ship an affected version, including nokogiri. It affects 3 products.

Products include Canonical Ubuntu Linux, Debian Debian Linux, Xmlsoft Libxml2.

How do I fix CVE-2015-8806?

Upgrade nokogiri to 1.6.8 or later.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2015-8806 being exploited?

There is no known exploitation of CVE-2015-8806 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-2015-8806, ECHO-a20a-0b3f-eaef, GHSA-7hp2-xwpj-95jq, UBUNTU-CVE-2015-8806.