Diskstation ManagerOperating system · Synology

CVE-2021-43927

CRITICAL · 9.8 CVSS v3.1 Published 2022-02-07
Fix available
A fix is available. Upgrade to 6.2.4-25556-3 / 7.0.1-42218-2 or later.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges 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
Improper neutralization of special elements used in an SQL command ('SQL Injection') vulnerability in Security Management functionality in Synology DiskStation Manager (DSM) before 7.0.1-42218-2 allows remote attackers to inject SQL commands via unspecified vectors.

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

SQL injection vulnerability in Synology DiskStation Manager's Security Management functionality allows remote attackers to inject arbitrary SQL commands. The vulnerability affects DSM versions prior to 7.0.1-42218-2 and can be exploited without authentication due to improper input validation in SQL queries.

MitigationApply Synology DSM update 7.0.1-42218-2 or later to patch the SQL injection vulnerability. As an interim measure, restrict network access to the DSM management interface and deploy WAF/IPS rules to detect and block SQL injection attempts.

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
Diskstation ManagerOperating system
Affected:>= 6.2, < 6.2.4-25556-3>= 7.0, < 7.0.1-42218-2

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

CVSS:3.1/AV:N/AC:L/PR:N/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. Identify DSM version
    Log into DSM web interface and go to Control Panel > Security > Security Status, or run command: cat /etc/VERSION on the device to see the exact version and build number
    Affected if The version is 6.2.x with build number below 25556-3, or 7.0.x with build number below 42218-2
  2. Confirm Security Management accessibility
    Verify the Security Management module (Control Panel > Security or the security.php endpoint) is reachable on the network
    Affected if The Security Management interface is exposed and accessible to remote attackers
  3. Check network exposure
    Review firewall rules and network configuration to determine if DSM management ports (5000, 5001, or web portal) are accessible from untrusted networks
    Affected if The DSM management interface is directly exposed to the internet or untrusted networks without access restrictions

You are affected if your DSM version falls below 6.2.4-25556-3 or 7.0.1-42218-2 AND the DSM management interface is network-accessible to potential attackers.

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 6.2.4-25556-3 / 7.0.1-42218-2 or later
Fixed in 6.2.4-25556-37.0.1-42218-2
Interim mitigation

Apply Synology DSM update 7.0.1-42218-2 or later to patch the SQL injection vulnerability. As an interim measure, restrict network access to the DSM management interface and deploy WAF/IPS rules to detect and block SQL injection attempts.

Recommended fix High confidence

DSM 6.2.4-25556-3 or DSM 7.0.1-42218-2

  1. Back up all critical data on your Synology NAS before proceeding with the update
  2. Log into DiskStation Manager as an administrator
  3. Navigate to Control Panel > Update & Restore > DSM Update
  4. Select the option to check for updates or manually download the update from Synology's download center
  5. For DSM 6.2.x users: Update to version 6.2.4-25556-3
  6. For DSM 7.0.x users: Update to version 7.0.1-42218-2
  7. Allow the update to complete and verify the system restarts successfully
  8. Confirm the installed DSM version matches the target fixed version
Caveat DSM major version upgrades may have compatibility impacts on packages and settings; review Synology's release notes before upgrading

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

Fix this in Diskstation Manager Scoped from the published advisory
  • Consultation2.0 h
  • Implementation1.0 h
  • Testing2.0 h
  • Review / QA1.0 h
6.0 hours of engineering $1,060
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,696.

Scan for this in your stack

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dbcve dependency scanner

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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-2021-43927 in production — separate from our analysis above.

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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
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  • No spam, self-promotion, credentials, or personal data