CVE-2025-20240 Cross-site scripting in Cisco IOS XE Software
An unauthenticated remote attacker can execute reflected XSS to steal user cookies from Cisco IOS XE devices via malicious links.
- 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-2025-20240?
CVE-2025-20240 is a medium-severity cross-site scripting vulnerability in Cisco IOS XE Software, published on 24 Sep 2025. 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
A vulnerability in the Web Authentication feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to conduct a reflected cross-site scripting attack (XSS) on an affected device. This vulnerability is due to improper sanitization of user-supplied input. An attacker could exploit this vulnerability by persuading a user to click a malicious link. A successful exploit could allow the attacker to execute a reflected XSS attack and steal user cookies from the affected device.
Weakness: CWE-692
Which versions are affected by CVE-2025-20240?
How do I fix CVE-2025-20240?
No fix has been published for CVE-2025-20240 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-2025-20240 being exploited?
There is no known exploitation of CVE-2025-20240 in the wild and no public exploit code.
Sources
Also known as GHSA-7423-xf8w-j7hg.