LineApplication · Linecorp

CVE-2021-36216

HIGH · 7.8 CVSS v3.1 Published 2021-09-08
Fix available
A fix is available. Upgrade to after 6.2.1.2289 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
LINE for Windows 6.2.1.2289 and before allows arbitrary code execution via malicious DLL injection.

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 hijacking vulnerability in LINE for Windows versions 6.2.1.2289 and prior, where the application loads dynamic link libraries from insecure locations. An attacker who can place a malicious DLL in a directory from which LINE loads DLLs can achieve arbitrary code execution with the privileges of the running user.

MitigationUpgrade LINE for Windows to a version newer than 6.2.1.2289. As a defense-in-depth measure, ensure users run with least privilege and monitor for suspicious DLLs in application directories.

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
LineApplication
Affected:<= 6.2.1.2289

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. Find installed LINE for Windows version
    Open Control Panel > Programs and Features, locate 'LINE' in the program list, and note the version number displayed in the Version column. Alternatively, right-click the LINE.exe file (typically in C:\Users\<username>\AppData\Local\LINE\bin\ or C:\Program Files\LINE\), select Properties, and check the Details tab for the Product Version.
    Affected if The version listed is 6.2.1.2289 or any earlier version number.
  2. Verify LINE executable location
    Locate the LINE.exe file on the system. Common paths include C:\Users\<username>\AppData\Local\LINE\bin\LINE.exe or C:\Program Files (x86)\LINE\bin\LINE.exe. Note the full path to the executable.
    Affected if LINE.exe exists on the system and is version 6.2.1.2289 or prior.
  3. Confirm vulnerable DLL loading behavior
    This vulnerability exists when the application loads DLLs from directories where unprivileged users have write access, such as the user AppData folder or application working directories. The vulnerable behavior is inherent to versions 6.2.1.2289 and prior - no specific configuration switch controls this; it is a flaw in how the application searches for and loads DLLs at runtime.
    Affected if LINE version is 6.2.1.2289 or earlier, meaning the application's DLL search path includes insecure locations.

A system is affected if LINE for Windows is installed with version 6.2.1.2289 or any earlier version, as these versions contain the DLL hijacking vulnerability.

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 a release after 6.2.1.2289
Interim mitigation

Upgrade LINE for Windows to a version newer than 6.2.1.2289. As a defense-in-depth measure, ensure users run with least privilege and monitor for suspicious DLLs in application directories.

Fix this in Line Scoped from the published advisory
  • Consultation3.0 h
  • Implementation6.0 h
  • Testing3.0 h
  • Review / QA2.0 h
14.0 hours of engineering $2,490
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,984.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2021-36216 — 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-2021-36216 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