Network Access ClientApplication · Barracuda

CVE-2021-42711

HIGH · 7.8 CVSS v3.1 Published 2021-12-01
Fix available
A fix is available. Upgrade to 5.2.2 or later.
See remediation →
80/100
Remediation priority · High
Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
Barracuda Network Access Client before 5.2.2 creates a Temporary File in a Directory with Insecure Permissions. This file is executed with SYSTEM privileges when an unprivileged user performs a repair operation.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

Barracuda Network Access Client before version 5.2.2 creates a temporary file in a directory with insecure permissions. When an unprivileged user initiates a repair operation, the application executes this temp file with SYSTEM-level privileges, enabling local privilege escalation from a standard user to full system control.

MitigationUpgrade Barracuda Network Access Client to version 5.2.2 or later to obtain the patch that addresses insecure temporary file creation and improper permission handling during repair operations.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Network Access ClientApplication
Affected:< 5.2.2

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Verify Barracuda Network Access Client is installed
    Check the program files directory or use system inventory tools to find Barracuda Network Access Client installation
    Affected if The application is present on the system
  2. Determine installed version number
    Open the application or check its executable properties to find the version, then compare to 5.2.2
    Affected if Version is lower than 5.2.2 (for example 5.2.1, 5.2.0, or earlier)
  3. Locate temporary files created during repair operations
    Run the repair function of the application and inspect the temporary directory where the app stores temp files during this operation
    Affected if Temp files exist in a directory with weak permissions (such as world-writable or accessible to all users)
  4. Verify repair operation accessibility for standard users
    Attempt to initiate a repair operation while logged in as a non-administrator user
    Affected if Unprivileged users can trigger the repair operation that executes temporary files

A user is affected if Barracuda Network Access Client version is below 5.2.2 and the repair operation can be initiated by a standard user who can then exploit the insecurely permissioned temp file for privilege escalation.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 5.2.2 or later
Fixed in 5.2.2
Interim mitigation

Upgrade Barracuda Network Access Client to version 5.2.2 or later to obtain the patch that addresses insecure temporary file creation and improper permission handling during repair operations.

Recommended fix Moderate confidence

Barracuda Network Access Client 5.2.2

  1. Identify the current installed version of Barracuda Network Access Client
  2. Download Barracuda Network Access Client version 5.2.2 or later from the official Barracuda Networks website or trusted distribution channel
  3. Backup the current configuration and any critical data
  4. Uninstall the current version of Barracuda Network Access Client
  5. Install version 5.2.2 or later of Barracuda Network Access Client
  6. Verify the installation was successful and the version is correct
  7. Test that the repair operation no longer creates insecure temporary files with elevated privileges
Caveat Review Barracuda release notes for any feature changes or known compatibility issues between your current version and 5.2.2

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Network Access Client Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing3.0 h
  • Review / QA2.0 h
11.0 hours of engineering $1,930
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,088.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2021-42711 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2021-42711 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data