CVE-2018-20821 Denial of service in n/a
Attackers can cause a denial of service in LibSass via uncontrolled recursion during CSS variable value parsing.
- 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-2018-20821?
CVE-2018-20821 is a medium-severity denial of service vulnerability in n/a, published on 23 Apr 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
The parsing component in LibSass through 3.5.5 allows attackers to cause a denial-of-service (uncontrolled recursion in Sass::Parser::parse_css_variable_value in parser.cpp).
Weakness: CWE-674
Which versions are affected by CVE-2018-20821?
It affects 1 product.
Products include Sass-Lang Libsass.
How do I fix CVE-2018-20821?
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-2018-20821 being exploited?
There is no known exploitation of CVE-2018-20821 in the wild and no public exploit code.
Other vulnerabilities in n/a
Sources
Also known as DEBIAN-CVE-2018-20821, GHSA-j7pw-5g39-c2cj, JLSEC-2026-504.