CVE-2025-1781 XML external entity in CSS Validator
An attacker can exploit an XML External Entity vulnerability in the W3C CSS Validator to perform SSRF and read arbitrary local files.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2025-1781?
CVE-2025-1781 is a high-severity vulnerability in W3C CSS Validator, published on 28 Mar 2025. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
There is a XXE in W3CSS Validator versions before cssval-20250226 that allows an attacker to use specially-crafted XML objects to coerce server-side request forgery (SSRF). This could be exploited to read arbitrary local files if an attacker has access to exception messages.
Weakness: CWE-611
Which versions are affected by CVE-2025-1781?
It affects 1 product.
Products include W3 Css Validator.
How do I fix CVE-2025-1781?
No fix has been published for CVE-2025-1781 yet. Limit exposure of the affected software until one is available.
Is CVE-2025-1781 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-1781 exists.