CVE-2021-27138

Exploitation

Not assessed. CISA has not published an exploitation assessment for this record, and it is not in the KEV catalog. That is an absence of assessment, not a finding of no risk.

SSVC decision

Not assessed by CISA

EPSS probability

1.10% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 65.6% of scored records. A rank, not a probability.

NVD base score

7.8 (CVSS v3.x), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

NVD analysis status

Modified. NVD last modified this record on 2026-06-17.

Red Hat severity

No Red Hat rating. Red Hat rates the CVEs that affect its products.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2021-02-17 22:36Z5 YR AGO

Last updated

2025-11-03 18:07Z12 MO AGO

Reserved

2021-02-10

Assigning CNA

mitre

Record state

PUBLISHED

Severity

High (CVSS 7.8)

CNA CVSS vector

CVSS:3.1/AC:L/AV:L/A:H/C:H/I:H/PR:N/S:U/UI:R

Weaknesses

No CWE assigned

Data version

5.2

Document digest

facfb651e04412b76966450fccb86afb6374e6e14fa38e1fcee3f84eb4a1e1e3

• github.comhttps://github.com/u-boot/u-boot/commit/b6f4c757959f8850e1299a77c8e5713da78e8ec0x_refsource_MISC
• github.comhttps://github.com/u-boot/u-boot/commit/3f04db891a353f4b127ed57279279f851c6b4917x_refsource_MISC
• github.comhttps://github.com/u-boot/u-boot/commit/79af75f7776fc20b0d7eb6afe1e27c00fdb4b9b4x_refsource_MISC
• lists.debian.orghttps://lists.debian.org/debian-lts-announce/2025/09/msg00037.html