CVE-2020-9363
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 · uneditedThe Sophos AV parsing engine before 2020-01-14 allows virus-detection bypass via a crafted ZIP archive. This affects Endpoint Protection, Cloud Optix, Mobile, Intercept X Endpoint, Intercept X for Server, and Secure Web Gateway. NOTE: the vendor feels that this does not apply to endpoint-protection products because the virus would be detected upon extraction.
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 confidenceSophos AV parsing engine before 2020-01-14 contains a flaw that allows crafted ZIP archives to bypass virus detection. The vulnerability exploits the parsing logic to hide malicious content from the scanner while still being extractable by the user.
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< 2020-01-14< 2020-01-14< 2020-01-14< 2020-01-14< 2020-01-14< 2020-01-14CVSS 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
- None
- User interaction
- Required
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/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 checksWork through these to decide whether this CVE applies to you.
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Identify installed Sophos productLocate the Sophos security product installed on the endpoint. Common locations: Control Panel > Programs and Features, or run 'wmic product get name,version' to list installed software. Look for one of: Sophos Cloud Optix, Sophos Endpoint Protection, Sophos Intercept X Endpoint, Sophos Intercept X For Server, Sophos Mobile, or Sophos Secure Web Gateway.Affected if No Sophos product from the affected list is installed, then this CVE does not apply.
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Determine Sophos AV engine versionOpen the Sophos console or use the built-in about/version utility for the installed product. For Endpoint Protection, right-click the Sophos icon in the system tray and select 'About' or 'Support Information'. Record the engine version or definition date shown.Affected if The engine version or definition date is before 2020-01-14, indicating the vulnerable parsing engine is in use.
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Verify ZIP archive scanning is activeOpen the Sophos management console and navigate to the scanning configuration settings. Check if archive scanning (specifically ZIP files) is enabled. This can also be verified via policy settings if centrally managed.Affected if ZIP archive scanning is disabled, the vulnerability is not exploitable in that specific configuration, but the outdated engine still poses risk.
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Confirm last successful updateCheck the Sophos update status in the main console or via the system tray icon. Look for 'Last update' timestamp or 'Virus definitions' date. This confirms whether the system has attempted to update past the 2020-01-14 patch date.Affected if The last update date is before 2020-01-14, meaning the system has not received the patched parsing engine.
The environment is affected if a listed Sophos product is installed with an AV engine or definition date prior to 2020-01-14 and ZIP archive scanning is enabled, allowing malicious ZIP archives to bypass detection.
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.
From vendor data2020-01-14
Update Sophos AV parsing engine to version after 2020-01-14. Additionally, enable extraction-time scanning or behavioral analysis as a defense-in-depth measure since the vendor indicates detection occurs upon extraction.
- Consultation1.0 h
- Implementation1.0 h
- Testing2.0 h
- Review / QA1.0 h
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Free · runs locallyCheck whether your project pulls in CVE-2020-9363 — 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-2020-9363 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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- Version or environment caveats, and links to real fixes
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