CVE-2021-3783 Cross-site Scripting (XSS) - Reflected in yourls/yourls
Attackers can inject malicious scripts into the Yourls URL shortener, potentially stealing user sessions or executing code in victim browsers.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2021-3783?
CVE-2021-3783 is a medium-severity cross-site scripting vulnerability in yourls/yourls, published on 15 Sep 2021. An attacker needs administrator access to exploit it, with no action from the victim.
Official description
yourls is vulnerable to Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Weakness: CWE-79
Which versions are affected by CVE-2021-3783?
2 open source packages ship an affected version, including yourls/yourls. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
yourls/yourls Packagist | All versions to 1.8.2 | None |
yourls/yourls Packagist | All versions to 1.8.2 | None |
Products include Yourls Yourls.
How do I fix CVE-2021-3783?
No fix has been published for CVE-2021-3783 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-2021-3783 being exploited?
There is no known exploitation of CVE-2021-3783 in the wild and no public exploit code.
Other vulnerabilities in yourls/yourls
- CVE-2019-14537 Access of Resource Using Incompatible Type ('Type Confusion') in yourls/yourls
- CVE-2021-3785 Cross-site Scripting (XSS) - Stored in yourls/yourls
- CVE-2021-3734 Improper Restriction of Rendered UI Layers or Frames in yourls/yourls
- CVE-2020-27388 YOURLS Stored Cross Site Scripting (XSS)
- CVE-2011-3824 Information disclosure in n/a
Sources
Also known as GHSA-cpq8-x35g-m439.