CVE-2021-21571

mediumpriority · track · 26EPSS 0.005 · 45 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.54% (45th) EPSS

CVSS 5.8 · medium

Is it mine?

129 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-27

Dell UEFI BIOS https stack leveraged by the Dell BIOSConnect feature and Dell HTTPS Boot feature contains an improper certificate validation vulnerability. A remote unauthenticated attacker may exploit this vulnerability using a person-in-the-middle attack which may lead to a denial of service and payload tampering.

cvss

Technical severity, 0–10. One row per scoring source.

6.5

010

base score 0–10 · higher = more severe · hover a vector to decode

v2.05.8mediumAV:N/AC:M/Au:N/C:N/I:P/A:Pprimary · NVD / NIST USexploitability 8.6 · impact 4.9

v3.16.5mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:Hprimary · NVD / NIST USexploitability 2.2 · impact 4.2

v3.15.9mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:Hsecondary · ENISA EU

v3.15.9mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:Hsecondary · security_alert@emc.comexploitability 1.6 · impact 4.2

v3.16mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-295USprimary

affected products (129)

Products and version ranges known to be affected.

Dell UEFI BIOS https stack≤ Gen 11, Gen 10enisa_euvdEU
dell alienware m15 r6 firmware< 1.3.3nvdUScpe:2.3:o:dell:alienware_m15_r6_firmware:*:*:*:*:*:*:*:*
dell chengming 3990 firmware< 1.4.1nvdUScpe:2.3:o:dell:chengming_3990_firmware:*:*:*:*:*:*:*:*
dell chengming 3991 firmware< 1.4.1nvdUScpe:2.3:o:dell:chengming_3991_firmware:*:*:*:*:*:*:*:*
dell g15 5510 firmware< 1.4.0nvdUScpe:2.3:o:dell:g15_5510_firmware:*:*:*:*:*:*:*:*
dell g15 5511 firmware< 1.3.3nvdUScpe:2.3:o:dell:g15_5511_firmware:*:*:*:*:*:*:*:*
dell g3 3500 firmware< 1.9.0nvdUScpe:2.3:o:dell:g3_3500_firmware:*:*:*:*:*:*:*:*
dell g5 5500 firmware< 1.9.0nvdUScpe:2.3:o:dell:g5_5500_firmware:*:*:*:*:*:*:*:*
dell g7 7500 firmware< 1.9.0nvdUScpe:2.3:o:dell:g7_7500_firmware:*:*:*:*:*:*:*:*
dell g7 7700 firmware< 1.9.0nvdUScpe:2.3:o:dell:g7_7700_firmware:*:*:*:*:*:*:*:*
dell inspiron 14 5418 firmware< 2.1.0_a06nvdUScpe:2.3:o:dell:inspiron_14_5418_firmware:*:*:*:*:*:*:*:*
dell inspiron 15 5518 firmware< 2.1.0_a06nvdUScpe:2.3:o:dell:inspiron_15_5518_firmware:*:*:*:*:*:*:*:*
dell inspiron 15 7510 firmware< 1.0.4nvdUScpe:2.3:o:dell:inspiron_15_7510_firmware:*:*:*:*:*:*:*:*
dell inspiron 3501 firmware< 1.6.0nvdUScpe:2.3:o:dell:inspiron_3501_firmware:*:*:*:*:*:*:*:*
dell inspiron 3880 firmware< 1.4.1nvdUScpe:2.3:o:dell:inspiron_3880_firmware:*:*:*:*:*:*:*:*
dell inspiron 3881 firmware< 1.4.1nvdUScpe:2.3:o:dell:inspiron_3881_firmware:*:*:*:*:*:*:*:*
dell inspiron 3891 firmware< 1.0.11nvdUScpe:2.3:o:dell:inspiron_3891_firmware:*:*:*:*:*:*:*:*
dell inspiron 5300 firmware< 1.7.1nvdUScpe:2.3:o:dell:inspiron_5300_firmware:*:*:*:*:*:*:*:*
dell inspiron 5301 firmware< 1.8.1nvdUScpe:2.3:o:dell:inspiron_5301_firmware:*:*:*:*:*:*:*:*
dell inspiron 5310 firmware< 2.1.0nvdUScpe:2.3:o:dell:inspiron_5310_firmware:*:*:*:*:*:*:*:*

showing 20 of 129

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd NVD CVE.org MITRE

published 2021-06-24modified 2026-06-17

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+1889 more

references (4)

External citations — patches, advisories, analysis.

scry

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