CVE-2024-34455

Cross-user file replacement via missing sticky bit

Published May 3, 2024 · Updated Aug 2, 2024

Incorrect default permissions in Buildroot before 0b2967e allow local users to delete or replace other users' /dev/shm files. The default package/skeleton-init-sysv/skeleton/etc/fstab mounts the world-writable tmpfs with mode 0777, omitting the sticky bit that restricts unlink and rename operations to file owners. The affected image must use BusyBox or SysV init; systemd-based images received the correct setting in Buildroot 2017.08, and the bounded impact is cross-user deletion or replacement of shared-memory files.

CVSS severity7.5
High
EPSS probability0.66%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Incorrect default permissions in Buildroot before 0b2967e allow local users to delete or replace other users' /dev/shm files. The default package/skeleton-init-sysv/skeleton/etc/fstab mounts the world-writable tmpfs with mode 0777, omitting the sticky bit that restricts unlink and rename operations to file owners. The affected image must use BusyBox or SysV init; systemd-based images received the correct setting in Buildroot 2017.08, and the bounded impact is cross-user deletion or replacement of shared-memory files.

The record

CVE
CVE-2024-34455
Published
May 3, 2024
Updated
Aug 2, 2024
Vendor
Buildroot
Product
Buildroot
Classifications
CWE-276, T1565.001
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. May 3, 2024CVE publishedPublication date reported by the CVE source.
  2. Aug 2, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <0b2967e

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Buildroot · Buildrootversion=0 <0b2967e

Published CVSS scores

7.5CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

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 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 exploitUnconfirmed

Weakness, pattern, technique

CWE-276Incorrect Default Permissions
T1565.001Stored Data Manipulation

Public exploit references

No public exploit references are available in this record.

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

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo