Vulnerability · Published Mar 25, 2026 · Assigned by cisco
CVE-2026-20125
High 7.7
In plain English
A high-severity security flaw in Cisco IOS XE Software from Cisco. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 22% of all known vulnerabilities).
Official description
A vulnerability in the HTTP Server feature of Cisco IOS Software and Cisco IOS XE Software Release 3E could allow an authenticated, remote attacker to cause an affected device to reload unexpectedly, resulting in a denial of service (DoS) condition. This vulnerability is due to improper validation of user-supplied input. An attacker could exploit this vulnerability by sending malformed HTTP requests to an affected device. A successful exploit could allow the attacker to cause a watchdog timer to expire and the device to reload, resulting in a DoS condition. To exploit this vulnerability, the attacker must have a valid user account.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Cisco | IOS | 12.2(33)CY12.2(33)CY112.2(33)CY212.2(55)SE12.2(55)SE312.2(55)SE212.2(58)SE12.2(55)SE1 |
| Cisco | Cisco IOS XE Software | 3.5.0E3.5.1E3.5.2E3.5.3E3.11.1S3.11.2S3.11.0S3.11.3S |
Weakness: CWE-228 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H