VDB-174447 · CVE-2021-21551 · dsa-2021-088

Dell DBUtil BIOS Driver dbutil_2_3.sys improper authorization

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
8.5	$0-$5k	0.00

Summaryinfo

A vulnerability was found in Dell DBUtil BIOS Driver. It has been rated as critical. This impacts an unknown function of the file dbutil_2_3.sys. Performing a manipulation results in improper authorization. This vulnerability is reported as CVE-2021-21551. The attack is possible to be carried out remotely. Moreover, an exploit is present.

Detailsinfo

A vulnerability classified as critical has been found in Dell DBUtil BIOS Driver (Hardware Driver Software) (version unknown). This affects an unknown function of the file dbutil_2_3.sys. The manipulation with an unknown input leads to a improper authorization vulnerability. CWE is classifying the issue as CWE-285. The product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action. This is going to have an impact on confidentiality, integrity, and availability.

The weakness was disclosed 05/04/2021 as dsa-2021-088. It is possible to read the advisory at dell.com. This vulnerability is uniquely identified as CVE-2021-21551. Technical details and a public exploit are known. The attack technique deployed by this issue is T1548.002 according to MITRE ATT&CK.

A public exploit has been developed by waldo-irc in C++ and been published 2 weeks after the advisory. The exploit is shared for download at github.com. It is declared as attacked. We expect the 0-day to have been worth approximately $5k-$25k. The CISA Known Exploited Vulnerabilities Catalog lists this issue since 03/31/2022 with a due date of 04/21/2022:

Apply updates per vendor instructions.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at Exploit-DB (49893). Further details are available at zdnet.com. Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

Hardware Driver Software

Vendor

Dell

Name

DBUtil BIOS Driver

License

commercial

Website

Vendor: https://www.dell.com/

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.5
VulDB Meta Temp Score: 8.5

VulDB Base Score: 8.8
VulDB Temp Score: 8.8
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.8
NVD Vector: 🔍

CNA Base Score: 8.8
CNA Vector (Dell): 🔍

CVSSv2info

AV	AC	Au	C	I	A
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💳	💳	💳	💳	💳	💳
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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Improper authorization
CWE: CWE-285 / CWE-266
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Yes

Availability: 🔍
Access: Public
Status: Attacked
Author: waldo-irc
Programming Language: 🔍
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

KEV Added: 🔍
KEV Due: 🔍
KEV Remediation: 🔍
KEV Ransomware: 🔍
KEV Notice: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Exploit-DB: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍
Exploit Delay Time: 🔍

Timelineinfo

01/04/2021 🔍
05/04/2021 +119 days 🔍
05/04/2021 +0 days 🔍
05/13/2021 +8 days 🔍
01/17/2025 +1345 days 🔍

Sourcesinfo

Vendor: dell.com

Advisory: dsa-2021-088
Status: Confirmed

CVE: CVE-2021-21551 (🔍)
GCVE (CVE): GCVE-0-2021-21551
GCVE (VulDB): GCVE-100-174447
scip Labs: https://www.scip.ch/en/?labs.20161013
Misc.: 🔍

Entryinfo

Created: 05/04/2021 22:32
Updated: 01/17/2025 02:17
Changes: 05/04/2021 22:32 (36), 05/06/2021 07:07 (3), 05/07/2021 14:33 (2), 05/07/2021 14:34 (1), 05/14/2021 06:40 (8), 04/25/2024 08:24 (25), 07/10/2024 00:34 (28), 09/19/2024 18:18 (2), 01/17/2025 02:17 (1)
Complete: 🔍
Committer: misc
Cache ID: 216::103