How severe is CVE-2021-3786?

CVE-2021-3786 has a CVSS 3.x base score of 4.4, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-3786 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (13th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-3786?

CVE-2021-3786 primarily affects Lenovo Thinkpad X380 Yoga Firmware. In total, 133 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-3786?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-3786 published?

CVE-2021-3786 was published on 2021-11-12 and last updated on 2026-06-17.

CVE-2021-3786

CVE-2021-3786 is a medium-severity vulnerability in Lenovo Thinkpad X380 Yoga Firmware with a CVSS 3.x base score of 4.4. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: Medium (CVSS 3.x base score 4.4)
CVSS v2: 2.1
EPSS exploit prediction: 0% (13th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Lenovo Thinkpad X380 Yoga Firmware
Published: 2021-11-12
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2021-3786?: 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.
How severe is CVE-2021-3786?: CVE-2021-3786 has a CVSS 3.x base score of 4.4, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-3786 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (13th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-3786?: CVE-2021-3786 primarily affects Lenovo Thinkpad X380 Yoga Firmware. In total, 133 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-3786?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-3786 published?: CVE-2021-3786 was published on 2021-11-12 and last updated on 2026-06-17.

References

https://support.lenovo.com/us/en/product_security/LEN-67440

Affected products (133)

cpe:2.3:o:lenovo:thinkpad_x380_yoga_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_x1_fold_gen_1_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_yoga_260_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_yoga_11e_3rd_gen_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_yoga_15_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_yoga_370_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_x12_detachable_gen_1_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_x390_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_yoga_11e_4th_gen_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_yoga_11e_5th_gen_firmware:*:*:*:*:geminilake-r:*:*:*
cpe:2.3:o:lenovo:thinkpad_x250_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_x260_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_x390_yoga_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_x280_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_x1_titanium_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_x270_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_x1_carbon_5th_gen_kabylake_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_x13_gen_1_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_x13_gen_2_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_x13_yoga_gen_1_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_x13_yoga_gen_2_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_x1_carbon_5th_gen_skylake_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_x1_yoga_1st_gen_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_x1_yoga_3rd_gen_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_x1_yoga_4th_gen_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_x1_yoga_gen_5_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_x1_carbon_4th_gen_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_10_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_x1_nano_gen_1_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_x1_extreme_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_x1_extreme_2nd_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_x1_extreme_gen_3_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_t460s_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_s2_gen_6_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_x1_carbon_gen_6_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_x1_carbon_gen_7_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_x1_carbon_gen_8_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_t560_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_t460p_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:lenovo:thinkpad_w550s_firmware:*:*:*:*:*:*:*:*

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