Insufficient entropy in IBM PowerVM Hypervisor

1) Insufficient Entropy

EUVDB-ID: #VU54502

Risk: Low

CVSSv4.0: 0.4 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-3505

CWE-ID: CWE-331 - Insufficient Entropy

Exploit availability: No

Description

The vulnerability allows a local user to decrypt data.

The vulnerability exists in the TPM 2 implementation, which returns 2048 bit keys with ~1984 bit strength due to a bug in the TCG specification. The bug is in the key creation algorithm in RsaAdjustPrimeCandidate(), which is called before the prime number check.

Mitigation

Install update from vendor's website.

Vulnerable software versions

PowerVM Hypervisor: before FW1050.00

CPE2.3

• cpe:2.3:a:ibm_corporation:powervm_hypervisor:*:*:*:*:*:*:*:*

External links

https://www.ibm.com/support/pages/node/7127519

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

How the attacker can exploit this vulnerability?

The attacker would have to trick the victim to open a a specially crafted file.

The attacker would have to login to the system and perform certain actions in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.