CVE-2012-0055

Local security-policy bypass via omitted inode checks

Published Feb 19, 2020 · Updated Aug 6, 2024

Missing inode security checks in OverlayFS before Ubuntu linux 3.0.0-16.27 allow local users to bypass policy and access restricted files. The filesystem omits extended inode permission checks required by cgroups and Linux Security Modules when mediating file access. A local account and a reachable OverlayFS mount are required; the bypass exposes files that the enforced policy should deny.

CVSS severity7.8
High
EPSS probability1.24%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Missing inode security checks in OverlayFS before Ubuntu linux 3.0.0-16.27 allow local users to bypass policy and access restricted files. The filesystem omits extended inode permission checks required by cgroups and Linux Security Modules when mediating file access. A local account and a reachable OverlayFS mount are required; the bypass exposes files that the enforced policy should deny.

The record

CVE
CVE-2012-0055
Published
Feb 19, 2020
Updated
Aug 6, 2024
Vendor
The Linux Kernel Organization
Product
OverlayFS
Classifications
T1005
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 19, 2020CVE publishedPublication date reported by the CVE source.
  2. Aug 6, 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?

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

  1. Affected versionversion=as used in Ubuntu 10.0.4 LTS and 11.10
  2. Affected versionversion=before 3.0.0-16.28

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · OverlayFSversion=as used in Ubuntu 10.0.4 LTS and 11.10; version=before 3.0.0-16.28

Published CVSS scores

7.8CanonicalCVSS:3.1/AV:L/AC:L/PR:L/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.

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 exploitUnconfirmed

Weakness, pattern, technique

T1005Data from Local System

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

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Your stack

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