Endpoint ProtectionApplication · Symantec

CVE-2020-5837

HIGH · 7.8 CVSS v3.1 Published 2020-05-11
Fix available
A fix is available. Upgrade to 14.3 or later.
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, prior to 14.3, may not respect file permissions when writing to log files that are replaced by symbolic links, which can lead to a potential elevation of privilege.

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 · high confidence

Symantec Endpoint Protection versions prior to 14.3 do not properly handle symbolic links when writing to log files. An attacker with local access could replace a log file with a symbolic link pointing to a sensitive file (such as a system binary or configuration), causing the security product to write to the target file with elevated privileges and achieve privilege escalation.

MitigationUpgrade Symantec Endpoint Protection to version 14.3 or later to obtain the patched version that enforces proper file permission validation when following symbolic links.

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:< 14.3

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. Verify Symantec Endpoint Protection is installed
    Check for SEP installation by looking for its process (smc.exe, Symantec Endpoint Protection Manager service) or checking Program Files for Symantec folder, or querying the Windows registry at HKLM\SOFTWARE\Symantec\Symantec Endpoint Protection\SMC\productversion
    Affected if Symantec Endpoint Protection is not installed on the system - this CVE only affects systems with SEP present
  2. Determine installed SEP version
    Open Windows Registry Editor and navigate to HKLM\SOFTWARE\Symantec\Symantec Endpoint Protection\SMC\productversion, or run 'smc -version' from the SEP client install directory, or check Programs and Features for Symantec Endpoint Protection version
    Affected if The installed version is any release prior to 14.3 (for example 14.2, 14.0, 12.x, or 11.x) - versions below 14.3 are vulnerable
  3. Confirm log writing functionality is active
    Check if SEP is actively running by verifying the SMC service status (services.msc) and reviewing if logging is enabled in the SEP client policy under 'Policy > Client Management > Settings > Logging'
    Affected if SEP is actively running with logging enabled - the vulnerability is only exploitable when the product writes to its log files while following symlinks
  4. Inspect log directory permissions
    Navigate to the SEP log directory (typically C:\ProgramData\Symantec\Symantec Endpoint Protection\CurrentVersion\Data\Logs or C:\Documents and Settings\All Users\Application Data\Symantec\Symantec Endpoint Protection\...\Logs) and check if non-admin users have write access to this location
    Affected if Users with limited privileges can write to the SEP log directory - combined with version < 14.3, this allows the symlink attack

A system is affected if it runs any version of Symantec Endpoint Protection prior to 14.3, has the log writing feature enabled, and allows non-privileged users to write files in the log directory.

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
Upgrade available Upgrade to 14.3 or later
Fixed in 14.3
Interim mitigation

Upgrade Symantec Endpoint Protection to version 14.3 or later to obtain the patched version that enforces proper file permission validation when following symbolic links.

Fix this in Endpoint Protection Scoped from the published advisory
  • Consultation3.0 h
  • Implementation4.0 h
  • Testing6.0 h
  • Review / QA3.0 h
16.0 hours of engineering $2,760
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $4,416.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2020-5837 — 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 sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2020-5837 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