Vulnerability · Published Oct 12, 2026 · Assigned by redhat
CVE-2026-52903YAML safe_load production fallback to unsafe_load enables RCE via deserialization
High 8.8
In plain English
A high-severity unsafe deserialization in ManageIQ from ManageIQ. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 39% of all known vulnerabilities).
Official description
A deserialization of untrusted data vulnerability was found in ManageIQ. The YamlLoadAliases module overrides YAML.safe_load to silently fall back to YAML.unsafe_load in production when a Psych::DisallowedClass error occurs. An authenticated attacker with dialog import access can exploit this to achieve remote code execution by uploading a crafted YAML payload that triggers the fallback and deserializes arbitrary Ruby objects. Red Hat CloudForms, which was based on ManageIQ, has reached End of Life and is no longer supported. No errata or patches will be issued. This CVE is being assigned for the benefit of the ManageIQ community and downstream consumers.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| ManageIQ | ManageIQ | 0 |
| Red Hat | Red Hat CloudForms | 0 |
Weakness: CWE-502 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H