CVE-2020-21583Public exploit

Local root command execution via PATH hijacking

Published Aug 22, 2023 · Updated Dec 20, 2024

Command injection in util-linux hwclock before 2.27 allows local users to execute arbitrary commands as root through the --date option. hwclock passes a command containing the bare date executable to popen(), which resolves it through the user-controlled PATH without dropping effective root privileges. The flaw is reachable only when an administrator has made hwclock setuid root, a non-default configuration; successful exploitation grants root command execution.

CVSS severity6.7
Medium
EPSS probability0.55%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Command injection in util-linux hwclock before 2.27 allows local users to execute arbitrary commands as root through the --date option. hwclock passes a command containing the bare date executable to popen(), which resolves it through the user-controlled PATH without dropping effective root privileges. The flaw is reachable only when an administrator has made hwclock setuid root, a non-default configuration; successful exploitation grants root command execution.

The record

CVE
CVE-2020-21583
Published
Aug 22, 2023
Updated
Dec 20, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-78, T1574.007
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 22, 2023CVE publishedPublication date reported by the CVE source.
  2. Dec 20, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

6.7NIST NVDCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-78Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
T1574.007Path Interception by PATH Environment Variable

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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