SB2025120853 - Multiple vulnerabilities in Citrix XenServer
Published: December 8, 2025
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 2 secuirty vulnerabilities.
1) Insufficient Entropy (CVE-ID: CVE-2025-62626)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to insufficient entropy in Zen 5 processors, which causes the RDSEED instruction to return 0 at a rate inconsistent with randomness while incorrectly signaling success (CF=1), indicating a potential misclassification of failure as success. A local user can escalate privileges on the system.
2) Improper Verification of Cryptographic Signature (CVE-ID: CVE-2024-36347)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to improper signature verification of x86 instruction execution. A local privileged user can load malicious microcode and execute it on the system.
Remediation
Install update from vendor's website.