CVE-2026-20308 Cisco IOS XE Software Web-Based Management Interface Vulnerability
An authenticated low-privilege attacker can cause a denial of service on Cisco IOS XE devices by sending crafted input to the web management interface.
- 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-2026-20308?
CVE-2026-20308 is a medium-severity denial of service vulnerability in Cisco IOS XE Software, published on 5 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
A vulnerability in the web-based management interface of Cisco IOS XE Software could allow an authenticated, remote attacker with low privileges to perform a denial of service (DoS) attack against an affected device. This vulnerability is due to insufficient input validation. An attacker could exploit this vulnerability by sending crafted input to the web-based management interface of an affected device. A successful exploit could allow the attacker to cause the web-based management interface to become unresponsive.
Weakness: CWE-269
Which versions are affected by CVE-2026-20308?
How do I fix CVE-2026-20308?
No fix has been published for CVE-2026-20308 yet. Limit exposure of the affected software until one is available.
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-2026-20308 being exploited?
There is no known exploitation of CVE-2026-20308 in the wild and no public exploit code.
Sources
Also known as GHSA-64g3-r786-fjmf.