CVE-2021-3155

Local information disclosure via permissive home directories

Published Feb 17, 2022 · Updated Aug 3, 2024

Incorrect permissions in Canonical snapd 2.54.2 and earlier allow local users to read private snap data from other users' home directories. createUserDataDirs created per-snap data paths without first creating the parent ~/snap directory with mode 0700, and user-session startup did not repair existing permissive directories. Exploitation requires a local account and another user's snap directory to retain group or other read permissions; the consequence is disclosure only.

CVSS severity3.8
Low
EPSS probability0.26%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Incorrect permissions in Canonical snapd 2.54.2 and earlier allow local users to read private snap data from other users' home directories. createUserDataDirs created per-snap data paths without first creating the parent ~/snap directory with mode 0700, and user-session startup did not repair existing permissive directories. Exploitation requires a local account and another user's snap directory to retain group or other read permissions; the consequence is disclosure only.

The record

CVE
CVE-2021-3155
Published
Feb 17, 2022
Updated
Aug 3, 2024
Vendor
Canonical
Product
snapd
Classifications
CWE-276, T1005
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 17, 2022CVE 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?

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  1. Affected versionversion=unspecified <=2.54.2

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Canonical · snapdversion=unspecified <=2.54.2

Published CVSS scores

3.8Canonical Ltd.CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N
5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
2.1NIST NVDAV:L/AC:L/Au:N/C:P/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.

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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 exploitUnconfirmed

Weakness, pattern, technique

CWE-276Incorrect Default Permissions
T1005Data from Local System

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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