Auth bypass in Apache Cloudstack
CVE-2026-50222
Missing Authorization, Exposure of Sensitive Information to an Unauthorized Actor vulnerability in Apache CloudStack's Userdata reference APIs. Several userdata-related APIs in Apache CloudStack, including deleteUserData, linkUserDataToTemplate, resetUserDataForVirtualMachine, deployVirtualMachine, and updateVirtualMachine, exhibit missing or insufficient access control validation, potentially allowing cross-tenant/cross-account access to userdata resources that belong to other tenants. This issue affects Apache CloudStack: from 4.18.0.0 through 4.20.3.0 and from 4.21.0.0 through 4.22.1.0. The deleteCniConfiguration API, introduced in 4.21.0.0, also exhibits similar behaviour and lacks access validation. Users are recommended to upgrade to version 4.20.3.1 or 4.22.1.1 or later, which fixes the issue.
Vulnerability class: Information Disclosure
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.
EPSS exploit prediction
EPSS: 0.005 (43.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 43rd percentile — 43.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.005 · change: +0.002
Affected products
Weakness classification (CWE)
References
- lists.apache.org/thread/g6cwddtjrwbh1d56wjz4cfp3fzfm4kbc (vendor-advisory, Mailing List, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-50222?
- CVE-2026-50222 is a high-severity vulnerability in Apache Cloudstack, classified under Information Disclosure. CVSS score: 7.5/10. Published 2026-08-21.
- How severe is CVE-2026-50222?
- High severity. CVSS v3 base score is 7.5 out of 10.