CVE-2019-11738 Security feature bypass in Firefox
Attackers can bypass Content Security Policy restrictions to execute malicious JavaScript in Firefox browsers using specific hash-based CSP directives.
- 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-2019-11738?
CVE-2019-11738 is a medium-severity vulnerability in Mozilla Firefox, published on 27 Sep 2019. 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 a Content Security Policy (CSP) directive is defined that uses a hash-based source that takes the empty string as input, execution of any javascript: URIs will be allowed. This could allow for malicious JavaScript content to be run, bypassing CSP permissions. This vulnerability affects Firefox < 69 and Firefox ESR < 68.1.
Which versions are affected by CVE-2019-11738?
It affects 3 products.
Products include Mozilla Firefox, Mozilla Firefox Esr, Opensuse Leap.
How do I fix CVE-2019-11738?
Upgrade to a fixed version.
Is CVE-2019-11738 being exploited?
There is no known exploitation of CVE-2019-11738 in the wild and no public exploit code.
Other vulnerabilities in Mozilla Firefox
Sources
Also known as DEBIAN-CVE-2019-11738, GHSA-v2rv-c5w8-f538, UBUNTU-CVE-2019-11738.