Quick answers
- Is CVE-2026-61398 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-61398 being exploited in the wild.
- How severe is CVE-2026-61398?
- Critical severity, with a CVSS score of 9.1, published 21 August 2026.
- Which products and versions are affected?
- Apache Cloudstack 4.15.1.0 through 4.20.3.0 and 4.21.0.0 through 4.22.1.0.
- Is there a fix for CVE-2026-61398?
- A patch was published on 2026-08-21: Fix available in versions 4.20.3.1, 4.22.1.1 and later Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-61398 attacked?
- It is attacked over the network, in a network appliance.
- Am I affected by CVE-2026-61398?
- Check whether you run Apache Cloudstack at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
This is an Improper Encoding or Escaping of Output vulnerability (CWE-116, related to XSS) in Apache CloudStack's web UI affecting the Instance Reset Password functionality. The vulnerability exists because user-controlled input is rendered in the UI without proper encoding or escaping, allowing an attacker to inject arbitrary code. An unauthenticated or low-privileged attacker with network access to the CloudStack management interface could craft a malicious payload to execute JavaScript in the context of an administrator's browser session. Successful exploitation could lead to account hijacking, credential theft, or further infrastructure compromise. Patches are available in versions 4.20.3.1, 4.22.1.1, and later.
Affected products
- Apache CloudStack 4.15.1.0 through 4.20.3.0 and 4.21.0.0 through 4.22.1.0
Timeline
- 2026-08-21: disclosed
- 2026-08-21: patched: Fix available in versions 4.20.3.1, 4.22.1.1 and later