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CiscoCVE-2026-20311

Cisco IOS XE Software: denial of service

Medium6.3CVE-2026-20311 · Published Aug 5, 2026 · updated Aug 6, 2026

A vulnerability in the web-based management interface of Cisco IOS XE Software could allow an authenticated, remote attacker with low privileges to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient error handling in the web-based management interface. An attacker could exploit this vulnerability by authenticating with a malformed certificate. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition.

Cisco advisory

Affected versions

PackageAffectedFixed in
Cisco IOS XE Software
Product
<= 17.3.1No fix yet
<= 17.3.1aNo fix yet
<= 17.3.2aNo fix yet
<= 17.3.1wNo fix yet
Details and references

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