WinscpApplication

CVE-2020-28864

CRITICAL · 9.8 CVSS v3.1 Published 2020-11-23
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges 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
Buffer overflow in WinSCP 5.17.8 allows a malicious FTP server to cause a denial of service or possibly have other unspecified impact via a long file name.

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

WinSCP 5.17.8 contains a buffer overflow vulnerability when processing file names received from an FTP server. A malicious server can send an excessively long file name to overflow a buffer, causing denial of service or potentially achieving code execution on the client machine.

MitigationOnly connect to trusted FTP servers and update WinSCP to the latest patched version. Users should avoid connecting to untrusted FTP sites until the vulnerability is remediated.

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
WinscpApplication
Affected:= 5.17.8

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
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/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 WinSCP version
    Open WinSCP, go to Help > About, or right-click the WinSCP.exe file and select Properties > Details to view the version number
    Affected if The installed version is exactly 5.17.8
  2. Confirm FTP protocol usage
    Review saved sessions in WinSCP Manager or check connection logs for sessions using FTP protocol (as opposed to SFTP or SCP)
    Affected if You connect to FTP servers using the FTP protocol in WinSCP
  3. Check for crash or异常 behavior logs
    Look in %APPDATA%\WinSCP\Logs for recent log files showing unexpected crashes or error messages related to file name processing
    Affected if Crashes or buffer overflow errors occur when receiving directory listings from FTP servers
  4. Review recent FTP server connections
    Examine WinSCP session logs or connection history for connections to untrusted or unknown FTP servers
    Affected if Connections to untrusted FTP servers have been established using the affected WinSCP version

You are affected if WinSCP version 5.17.8 is installed AND you use it to connect to FTP servers.

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

Only connect to trusted FTP servers and update WinSCP to the latest patched version. Users should avoid connecting to untrusted FTP sites until the vulnerability is remediated.

Fix this in Winscp Scoped from the published advisory
  • Consultation1.0 h
  • Implementation1.0 h
  • Testing1.0 h
  • Review / QA1.0 h
4.0 hours of engineering $750
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Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2020-28864 — 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-2020-28864 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