CVE-2021-27223
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 · uneditedA denial-of-service issue existed in one of modules that was incorporated in Kaspersky Anti-Virus products for home and Kaspersky Endpoint Security. A local user could cause Windows crash by running a specially crafted binary module. The fix was delivered automatically. Credits: (Straghkov Denis, Kurmangaleev Shamil, Fedotov Andrey, Kuts Daniil, Mishechkin Maxim, Akolzin Vitaliy) @ ISPRAS
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 confidenceThis is a local denial-of-service vulnerability in Kaspersky Anti-Virus products (home and endpoint). A local authenticated user can cause a Windows crash by executing a specially crafted binary module, triggering a fault in one of the incorporated AV modules.
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< 2021-06< 2021-06< 2021-06< 2021-06< 2021-06< 2021-06CVSS 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
- None
- Integrity
- None
- Availability
- High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/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 checksWork through these to decide whether this CVE applies to you.
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Identify installed Kaspersky productOpen Windows Control Panel > Programs and Features, or run 'Get-ItemProperty HKLM:\Software\Microsoft\Windows\CurrentVersion\Uninstall\* | Select-Object DisplayName, DisplayVersion' in PowerShell to list installed software. Look for Kaspersky Anti-Virus, Kaspersky Endpoint Security, Kaspersky Internet Security, Kaspersky Security Cloud, Kaspersky Small Office Security, or Kaspersky Total Security.Affected if No Kaspersky product is found in the installed programs list, then this CVE does not apply to the system.
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Check installed product versionRight-click the Kaspersky icon in the system tray and select 'About', or open the Kaspersky application and navigate to Help > About. Record the full version number and build date.Affected if The version number is not displayed or cannot be determined, manual verification of the installed files may be required.
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Compare version against vulnerability thresholdVerify if the installed version is below the 2021-06 release. The affected versions are any build or version released before June 2021. Compare your recorded version and build date from the previous step against the June 2021 cutoff.Affected if The installed version is a build released before June 2021, indicating the system is within the affected version range.
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Confirm product edition typeDetermine whether the installed product is a home user product (Anti-Virus, Internet Security, Total Security, Security Cloud, Small Office Security) or an enterprise product (Endpoint Security). This confirms the product matches one of the listed affected variants.Affected if The installed product matches one of the home or endpoint products listed in the affected products, and the version is below 2021-06.
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Review Windows crash dumpsCheck for crash dump files in C:\Windows\Minidump or C:\Windows\MEMORY.DMP. Also review Windows Event Viewer under Windows Logs > System for Event ID 1001 (Bugcheck) or Application Error events occurring around the time of the suspected incident.Affected if Crash dumps exist and reference Kaspersky AV modules in the stack trace or error details, this may indicate exploitation of this vulnerability.
A system is affected if it runs any of the listed Kaspersky products with a version released before June 2021, and a local authenticated user has executed a specially crafted binary that triggered the AV module crash.
Generated from the published advisory. Verify against your own configuration.
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 · scoped2021-06
Kaspersky delivered an automatic update to address this vulnerability. Organizations should verify that endpoint protection clients have received and applied the latest signature/engine updates, and ensure Windows crash dump collections are reviewed to detect any exploitation attempts.
Kaspersky products 2021-06 or later (Anti Virus 2021-06+, Endpoint Security 2021-06+, Internet Security 2021-06+, Security Cloud 2021-06+, Small Office Security 2021-06+, Total Security 2021-06+)
- Upgrade to Kaspersky product version 2021-06 or later. The fix was delivered automatically via Kaspersky's update infrastructure, but if affected, ensure automatic updates are enabled and allow the product to update to the June 2021 release or subsequent versions.
- Verify the installed version by opening the main product window and checking the version number in About or Settings.
- Confirm the version is 2021-06 or higher (e.g., 2021-06-xx or later releases).
- If automatic updates are disabled, enable them in Settings > Protection > Updates, or manually trigger an update to receive the patched version.
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation2.0 h
- Implementation1.0 h
- Testing2.0 h
- Review / QA1.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-27223 — 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 sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2021-27223 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- 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