6.4

CVE-2021-20261: linux linux_kernel

Modified
AliasesUBUNTU-CVE-2021-20261DEBIAN-CVE-2021-20261
Published 11-03-2021Last modified 03-08-2024

Vulnerability summary

CVE-2021-20261 is a medium (CVSS 6.4) vulnerability in linux linux_kernel. EPSS estimates a 0.23% chance of exploitation in the next 30 days, higher than 13.5% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 6.4, local access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
6.4/10
010
Medium · v3.1 (NVD)
EPSS score
0.23%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 2 · Related 2
SUSE-SU-2021:14724-1USN-4904-1

Timeline

  1. 11-03-2021
    PublishedVulnerability first disclosed.
  2. 03-08-2024
    Last modifiedVulnerability information updated.

Description

A race condition was found in the Linux kernels implementation of the floppy disk drive controller driver software. The impact of this issue is lessened by the fact that the default permissions on the floppy device (/dev/fd0) are restricted to root. If the permissions on the device have changed the impact changes greatly. In the default configuration root (or equivalent) permissions are required to attack this flaw.

CVSS metrics

4 scores · 3 sources · 2 versions

EPSS trend

Probability

0.23%

Chance of exploitation in the next 30 days

Percentile

14%

Versus all other CVEs

30-day change

No change 0.00 pp

From 0.23% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: local access, administrative account, no user interaction (CVSS vector). Other conditions: not stated in public data.

Ubuntu28 products
  • linuxAll versions (No fix recorded) | < 4.4.0-208.240
  • linux-aws< 4.4.0-1090.94 | < 4.4.0-1126.140
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.3All versions (No fix recorded)
  • linux-azureAll versions (No fix recorded)
Debian1 product
  • linux< 4.5.1-1
Linux1 product
  • linux_kernel< 4.5 | 4.5 | 4.5:rc1 | 4.5:rc2 | 4.5:rc3 | 4.5:rc4
Redhat1 product

4 vendors · 31 products

References

7 links