CVE-2017-7783 Denial of service in Firefox
An attacker can cause Firefox to hang or crash by using a long username in a site URL, resulting in a denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2017-7783?
CVE-2017-7783 is a high-severity denial of service vulnerability in Mozilla Firefox, published on 11 Jun 2018. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
If a long user name is used in a username/password combination in a site URL (such as " http://UserName:[email protected]"), the resulting modal prompt will hang in a non-responsive state or crash, causing a denial of service. This vulnerability affects Firefox < 55.
Weakness: CWE-20
Which versions are affected by CVE-2017-7783?
It affects 1 product.
Products include Mozilla Firefox.
How do I fix CVE-2017-7783?
Upgrade to a fixed version.
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-2017-7783 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2017-7783 exists.
Public exploit code: 1 Exploit-DB entry.
Other vulnerabilities in Mozilla Firefox
Sources
Also known as GHSA-ch5f-5368-9hw8, UBUNTU-CVE-2017-7783.