CVE-2021-20813 Cross-site scripting in Movable Type
Remote attackers can inject arbitrary scripts into the Content Data edit screen of Movable Type, potentially compromising user sessions or data.
- 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
- None listed
What is CVE-2021-20813?
CVE-2021-20813 is a medium-severity cross-site scripting vulnerability in Six Apart Ltd. Movable Type, published on 26 Aug 2021. 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
Cross-site scripting vulnerability in Edit screen of Content Data of Movable Type (Movable Type 7 r.4903 and earlier (Movable Type 7 Series) and Movable Type Advanced 7 r.4903 and earlier (Movable Type Advanced 7 Series)) allows remote attackers to inject arbitrary script or HTML via unspecified vectors.
Weakness: CWE-79
Which versions are affected by CVE-2021-20813?
It affects 1 product.
Products include Sixapart Movable Type.
How do I fix CVE-2021-20813?
No fix has been published for CVE-2021-20813 yet. Limit exposure of the affected software until one is available.
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-2021-20813 being exploited?
There is no known exploitation of CVE-2021-20813 in the wild and no public exploit code.
Other vulnerabilities in Six Apart Ltd. Movable Type
Sources
Also known as GHSA-8p38-cjxc-8fxx.