CVE-2021-31154Public exploit

Local root escalation via predictable temporary paths

Published May 27, 2021 · Updated Aug 3, 2024

Symlink following in pleaseedit in pleaser before 0.4 allows local users to gain root privileges through predictable temporary files. The tmp_edit_file_name and source_tmp_file_name paths are predictable, and privileged openat calls omit O_NOFOLLOW before chown or overwrite operations. Exploitation requires pleaseedit authorization and either winning a race where kernel symlink protections do not block it or controlling the target directory with a cooperating account.

CVSS severity7.8
High
EPSS probability0.47%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Symlink following in pleaseedit in pleaser before 0.4 allows local users to gain root privileges through predictable temporary files. The tmp_edit_file_name and source_tmp_file_name paths are predictable, and privileged openat calls omit O_NOFOLLOW before chown or overwrite operations. Exploitation requires pleaseedit authorization and either winning a race where kernel symlink protections do not block it or controlling the target directory with a cooperating account.

The record

CVE
CVE-2021-31154
Published
May 27, 2021
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-340, CWE-59, T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. May 27, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 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

7.8NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
7.2NIST NVDAV:L/AC:L/Au:N/C:C/I:C/A:C

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-340Generation of Predictable Numbers or Identifiers
CWE-59Improper Link Resolution Before File Access ('Link Following')
T1068Exploitation for Privilege Escalation

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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