MdaemonApplication · Altn

CVE-2021-27181

HIGH · 8.8 CVSS v3.1 Published 2021-04-14
Fix available
A fix is available. Upgrade to 20.0.4 or later.
See remediation →
95/100
Remediation priority · Urgent
Public exploit Remotely reachable No privileges

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
An issue was discovered in MDaemon before 20.0.4. Remote Administration allows an attacker to perform a fixation of the anti-CSRF token. In order to exploit this issue, the user has to click on a malicious URL provided by the attacker and successfully authenticate into the application. Having the value of the anti-CSRF token, the attacker may trick the user into visiting his malicious page and performing any request with the privileges of attacked user.

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
How this class of weakness works · CWE-352

The application can't tell whether a state-changing request was genuinely intended by the user, so an attacker can trick a logged-in victim's browser into making it. That can transfer funds, change settings, or create accounts silently. Remediation is anti-CSRF tokens — or equivalent same-site protections — on every state-changing request.

General guidance for the cross-site request forgery (csrf) class — the official description and references above are authoritative for this specific CVE. Want a bespoke review and a reviewed fix? Ask our team →

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
MdaemonApplication
Affected:< 20.0.4

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
Network
Complexity
Low
Privileges
None
User interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

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

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 20.0.4 or later
Fixed in 20.0.4
Recommended fix High confidence

Mdaemon 20.0.4 or later

  1. Backup the current MDaemon configuration and all user data
  2. Download MDaemon version 20.0.4 or later from the official vendor website (www.altn.com)
  3. Stop the MDaemon service
  4. Install the downloaded version 20.0.4 or later over the existing installation
  5. Restart the MDaemon service
  6. Verify the Remote Administration interface is accessible and functioning normally
Caveat Security patch upgrade; minimal risk, but test in non-production environment first if possible

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

We can perform the upgrade in your staging environment and verify nothing breaks — typical engagement from $1,950. Get the upgrade done

Scan for this in your stack

Free · runs locally
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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-2021-27181 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