CVE-2021-3786

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-11-12 · updated 2026-06-17
Weakness: CWE-20

Description

A potential vulnerability in the SMI callback function used in CSME configuration of some Lenovo Notebook and ThinkPad systems could be used to leak out data out of the SMRAM range.

Affected products

Lenovo Ideapad S940-14Iwl Firmware: through 12.0.81.1753
Lenovo Ideapad Yoga S940-14Iwl Firmware: through 12.0.81.1753
Lenovo Thinkpad 10 Firmware: before 2021-10-25 — fixed in 2021-10-25
Lenovo Thinkpad 11E 3Rd Gen Firmware: before 2021-10-31 — fixed in 2021-10-31
Lenovo Thinkpad 11E 4Th Gen Firmware: before 2021-10-31 — fixed in 2021-10-31
Lenovo Thinkpad 11E Yoga Gen 6 Firmware: before 2021-10-31 — fixed in 2021-10-31
Lenovo Thinkpad 13 Gen 2 Firmware: before 2021-10-31 — fixed in 2021-10-31
Lenovo Thinkpad 25 Firmware: before n1qet92w — fixed in n1qet92w
Lenovo Thinkpad E14 Firmware: through 2021-10-15
Lenovo Thinkpad E14 Gen 2 Firmware: before 2021-10-15 — fixed in 2021-10-15
Lenovo Thinkpad E14 Gen 3 Firmware: before 2021-10-15 — fixed in 2021-10-15
Lenovo Thinkpad E15 Firmware: before 2021-10-15 — fixed in 2021-10-15
Lenovo Thinkpad E15 Gen 2 Firmware: before 2021-10-15 — fixed in 2021-10-15
Lenovo Thinkpad E15 Gen 3 Firmware: before 2021-10-15 — fixed in 2021-10-15
Lenovo Thinkpad E470 Firmware: before 2021-10-15 — fixed in 2021-10-15
Lenovo Thinkpad E480 Firmware: before 2021-10-15 — fixed in 2021-10-15
Lenovo Thinkpad E490 Firmware: before 2021-10-15 — fixed in 2021-10-15
Lenovo Thinkpad E570 Firmware: before 2021-10-15 — fixed in 2021-10-15
Lenovo Thinkpad E580 Firmware: before 2021-10-15 — fixed in 2021-10-15
Lenovo Thinkpad E590 Firmware: before 2021-10-15 — fixed in 2021-10-15
Lenovo Thinkpad Helix Firmware: before n17etb6w — fixed in n17etb6w
Lenovo Thinkpad L13 Firmware: before 2021-10-31 — fixed in 2021-10-31
Lenovo Thinkpad L13 Gen 2 Firmware: before 2021-10-31 — fixed in 2021-10-31
Lenovo Thinkpad L13 Yoga Firmware: before 2021-10-31 — fixed in 2021-10-31
Lenovo Thinkpad L13 Yoga Gen 2 Firmware: before 2021-10-31 — fixed in 2021-10-31
Lenovo Thinkpad L14 Firmware: before 2021-10-15 — fixed in 2021-10-15
Lenovo Thinkpad L15 Firmware: before 2021-10-15 — fixed in 2021-10-15
Lenovo Thinkpad L15 Gen 2 Firmware: before 2021-10-15 — fixed in 2021-10-15
Lenovo Thinkpad L380 Firmware: before 2021-10-31 — fixed in 2021-10-31
Lenovo Thinkpad L380 Yoga Firmware: before 2021-10-31 — fixed in 2021-10-31

How to fix

Upgrade to a fixed version: Lenovo Thinkpad 10 Firmware 2021-10-25; Lenovo Thinkpad 11E 3Rd Gen Firmware 2021-10-31; Lenovo Thinkpad 11E 4Th Gen Firmware 2021-10-31; Lenovo Thinkpad 11E Yoga Gen 6 Firmware 2021-10-31; Lenovo Thinkpad 13 Gen 2 Firmware 2021-10-31; Lenovo Thinkpad 25 Firmware n1qet92w; Lenovo Thinkpad E14 Gen 2 Firmware 2021-10-15; Lenovo Thinkpad E14 Gen 3 Firmware 2021-10-15; Lenovo Thinkpad E15 Firmware 2021-10-15; Lenovo Thinkpad E15 Gen 2 Firmware 2021-10-15; Lenovo Thinkpad E15 Gen 3 Firmware 2021-10-15; Lenovo Thinkpad E470 Firmware 2021-10-15. Check the vendor advisory for mitigations.

References

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