CVE-2017-7834 Cross-site scripting in Firefox
Attackers can bypass Content Security Policy and execute JavaScript via data URLs in new tabs, potentially leading to cross-site scripting attacks in Firefox.
- 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-2017-7834?
CVE-2017-7834 is a medium-severity cross-site scripting vulnerability in Mozilla Firefox, published on 11 Jun 2018. 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
A "data:" URL loaded in a new tab did not inherit the Content Security Policy (CSP) of the original page, allowing for bypasses of the policy including the execution of JavaScript. In prior versions when "data:" documents also inherited the context of the original page this would allow for potential cross-site scripting (XSS) attacks. This vulnerability affects Firefox < 57.
Weakness: CWE-79
Which versions are affected by CVE-2017-7834?
It affects 1 product.
Products include Mozilla Firefox.
How do I fix CVE-2017-7834?
Upgrade to a fixed version.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2017-7834 being exploited?
There is no known exploitation of CVE-2017-7834 in the wild and no public exploit code.
Other vulnerabilities in Mozilla Firefox
Sources
Also known as GHSA-5q3m-44wf-w4hc, UBUNTU-CVE-2017-7834.