#VU66212 Time-of-check Time-of-use (TOCTOU) Race Condition in iDRAC9 - CVE-2021-21539

Vulnerability identifier: #VU66212

Vulnerability risk: Low

CVSSv4.0: 4.4 [CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-21539

CWE-ID: CWE-367

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
iDRAC9
Web applications / Remote management & hosting panels

Vendor: Dell

Description

The vulnerability allows a remote user to escalate privileges on the system.

The vulnerability exists due to a Time-of-check Time-of-use (TOCTOU) race condition. A remote unauthenticated attacker can exploit this vulnerability to gain elevated privileges when a user with higher privileges is simultaneously accessing iDRAC through the web interface.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

iDRAC9: 2.65.65.65 - 4.40.35.00

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External links
https://www.dell.com/support/kbdoc/000185293

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

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