CVE-2026-61398

Critical

Description

Improper Encoding or Escaping of Output vulnerability in Apache CloudStack's UI while using Instance Reset Password functionality. This issue affects Apache CloudStack: from 4.15.1.0 through 4.20.3.0 and from 4.21.0.0 through 4.22.1.0. Users are recommended to upgrade to version 4.20.3.1 or 4.22.1.1 or later, which fixes the issue.

SeverityCritical

CVSS9.1

Exploit probability—

Product

Apache Cloudstack

PublishedAug 21, 2026

First seenAug 21, 2026

Weakness typeCWE-116CWE-116

How to fix

Update

apache cloudstack4.20.3.1, 4.22.1.1 or later

Vendor advisories

lists.apache.org/thread/g6cwddtjrwbh1d56wjz4cfp3fzfm4kbc

Affected products

Product	Affected versions	Fixed in
apache cloudstack	4.15.1.0 ≤ v < 4.20.3.1, 4.21.0.0 ≤ v < 4.22.1.1	4.20.3.1, 4.22.1.1

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