CVE-2021-21573

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-06-24 · updated 2026-06-17
Weakness: CWE-121

Description

Dell BIOSConnect feature contains a buffer overflow vulnerability. An authenticated malicious admin user with local access to the system may potentially exploit this vulnerability to run arbitrary code and bypass UEFI restrictions.

Affected products

Dell Alienware M15 R6 Firmware: before 1.3.3 — fixed in 1.3.3
Dell Chengming 3990 Firmware: before 1.4.1 — fixed in 1.4.1
Dell Chengming 3991 Firmware: before 1.4.1 — fixed in 1.4.1
Dell G15 5510 Firmware: before 1.4.0 — fixed in 1.4.0
Dell G15 5511 Firmware: before 1.3.3 — fixed in 1.3.3
Dell G3 3500 Firmware: through 1.9.0
Dell G5 5500 Firmware: before 1.9.0 — fixed in 1.9.0
Dell G7 7500 Firmware: before 1.9.0 — fixed in 1.9.0
Dell G7 7700 Firmware: before 1.9.0 — fixed in 1.9.0
Dell Inspiron 14 5418 Firmware: before 2.1.0_a06 — fixed in 2.1.0_a06
Dell Inspiron 15 5518 Firmware: before 2.1.0_a06 — fixed in 2.1.0_a06
Dell Inspiron 15 7510 Firmware: before 1.0.4 — fixed in 1.0.4
Dell Inspiron 3501 Firmware: before 1.6.0 — fixed in 1.6.0
Dell Inspiron 3880 Firmware: before 1.4.1 — fixed in 1.4.1
Dell Inspiron 3881 Firmware: before 1.4.1 — fixed in 1.4.1
Dell Inspiron 3891 Firmware: before 1.0.11 — fixed in 1.0.11
Dell Inspiron 5300 Firmware: before 1.7.1 — fixed in 1.7.1
Dell Inspiron 5301 Firmware: before 1.8.1 — fixed in 1.8.1
Dell Inspiron 5310 Firmware: before 2.1.0 — fixed in 2.1.0
Dell Inspiron 5400 2-In-1 Firmware: before 1.7.0 — fixed in 1.7.0
Dell Inspiron 5400 Aio Firmware: before 1.4.0 — fixed in 1.4.0
Dell Inspiron 5401 Aio Firmware: before 1.4.0 — fixed in 1.4.0
Dell Inspiron 5401 Firmware: before 1.7.2 — fixed in 1.7.2
Dell Inspiron 5402 Firmware: before 1.5.1 — fixed in 1.5.1
Dell Inspiron 5406 2N1 Firmware: before 1.5.1 — fixed in 1.5.1
Dell Inspiron 5408 Firmware: before 1.7.2 — fixed in 1.7.2
Dell Inspiron 5409 Firmware: before 1.5.1 — fixed in 1.5.1
Dell Inspiron 5410 2-In-1 Firmware: before 2.1.0 — fixed in 2.1.0
Dell Inspiron 5501 Firmware: before 1.7.2 — fixed in 1.7.2
Dell Inspiron 5502 Firmware: before 1.5.1 — fixed in 1.5.1

How to fix

Upgrade to a fixed version: Dell Alienware M15 R6 Firmware 1.3.3; Dell Chengming 3990 Firmware 1.4.1; Dell Chengming 3991 Firmware 1.4.1; Dell G15 5510 Firmware 1.4.0; Dell G15 5511 Firmware 1.3.3; Dell G5 5500 Firmware 1.9.0; Dell G7 7500 Firmware 1.9.0; Dell G7 7700 Firmware 1.9.0; Dell Inspiron 14 5418 Firmware 2.1.0_a06; Dell Inspiron 15 5518 Firmware 2.1.0_a06; Dell Inspiron 15 7510 Firmware 1.0.4; Dell Inspiron 3501 Firmware 1.6.0. Check the vendor advisory for mitigations.

References

Get alerted when CVE-2021-21573 or the next vulnerability affects your stack