CVE-2019-17020 Security feature bypass in Firefox
Firefox fails to apply Content Security Policy to XSL stylesheets in XML files, allowing JavaScript execution that bypasses security restrictions.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2019-17020?
CVE-2019-17020 is a medium-severity vulnerability in Canonical Ubuntu Linux, published on 8 Jan 2020. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
If an XML file is served with a Content Security Policy and the XML file includes an XSL stylesheet, the Content Security Policy will not be applied to the contents of the XSL stylesheet. If the XSL sheet e.g. includes JavaScript, it would bypass any of the restrictions of the Content Security Policy applied to the XML document. This vulnerability affects Firefox < 72.
Weakness: CWE-611
Which versions are affected by CVE-2019-17020?
It affects 2 products.
Products include Canonical Ubuntu Linux, Mozilla Firefox.
How do I fix CVE-2019-17020?
Upgrade to a fixed version.
Is CVE-2019-17020 being exploited?
There is no known exploitation of CVE-2019-17020 in the wild and no public exploit code.
Other vulnerabilities in Canonical Ubuntu Linux
Sources
Also known as GHSA-p8vh-p3hc-xm35, UBUNTU-CVE-2019-17020.