Endpoint ProtectionApplication · Symantec

CVE-2020-5821

HIGH · 7.8 CVSS v3.1 Published 2020-02-11
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
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
Symantec Endpoint Protection (SEP) and Symantec Endpoint Protection Small Business Edition (SEP SBE), prior to 14.2 RU2 MP1 and prior to 14.2.5569.2100 respectively, may be susceptible to a DLL injection vulnerability, which is a type of issue whereby an individual attempts to execute their own code in place of legitimate code as a means to perform an exploit.

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

This is a DLL injection vulnerability in Symantec Endpoint Protection and Symantec Endpoint Protection Small Business Edition. An attacker could exploit this to execute arbitrary code by injecting their own code into legitimate DLLs. The vulnerability exists in versions prior to 14.2 RU2 MP1 for SEP and prior to 14.2.5569.2100 for SEP SBE.

MitigationUpdate Symantec Endpoint Protection to version 14.2 RU2 MP1 or later (for SEP SBE to 14.2.5569.2100 or later) to remediate this vulnerability.

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
Endpoint ProtectionApplication
Affected:= 11.0= 12.1= 14.0.0= 14.0.1= 14.2= 12.0

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. Check installed SEP version via registry
    Open Windows Registry Editor and navigate to HKLM\SOFTWARE\Symantec\Symantec Endpoint Protection\CurrentVersion. Look for the "ProductVersion" value.
    Affected if ProductVersion shows 11.0, 12.0, 12.1, 14.0.0, 14.0.1, or 14.2 without RU2 MP1 applied
  2. Check SEP build number
    In the same registry path, locate the "ProductBuild" or "Version" value to get the full build number (e.g., 14.2.xxxx).
    Affected if Build number is below the fixed versions (14.2 RU2 MP1 for SEP, 14.2.5569.2100 for SEP SBE)
  3. Verify SEP SBE version if using Small Business Edition
    Check HKLM\SOFTWARE\Symantec\Symantec Endpoint Protection\SBE\CurrentVersion for the "ProductVersion" value.
    Affected if Version is any build prior to 14.2.5569.2100
  4. Confirm via SymCorp UI if available
    Open the Symantec Endpoint Protection client, click Help, then About Symantec Endpoint Protection to view the exact version and build number.
    Affected if Version displayed is any release prior to 14.2 RU2 MP1 (for SEP) or prior to 14.2.5569.2100 (for SEP SBE)

The environment is affected if the installed Symantec Endpoint Protection version is 11.0, 12.0, 12.1, 14.0.x, or 14.2 prior to RU2 MP1, or SEP SBE prior to 14.2.5569.2100.

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.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Update Symantec Endpoint Protection to version 14.2 RU2 MP1 or later (for SEP SBE to 14.2.5569.2100 or later) to remediate this vulnerability.

Fix this in Endpoint Protection Scoped from the published advisory
  • Consultation4.0 h
  • Implementation12.0 h
  • Testing8.0 h
  • Review / QA4.0 h
28.0 hours of engineering $4,880
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Scan for this in your stack

Free · runs locally
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-2020-5821 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
  • No weaponised exploit code, or anything meant to cause harm
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