CVE-2020-8634Public exploit

Local privilege escalation via world-writable file saves

Published Mar 6, 2020 · Updated Aug 4, 2024

Improper permission preservation in Wing FTP Server 6.2.3 allows local users to gain root access via HTTP file management. The HTTP file editor saves modified files with mode 666, replacing prior restrictions with world-readable and world-writable permissions. Exploitation requires local access and a privileged Wing FTP user to edit a sensitive file through HTTP; the resulting write access supports escalation to root.

CVSS severity7.8
High
EPSS probability0.43%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper permission preservation in Wing FTP Server 6.2.3 allows local users to gain root access via HTTP file management. The HTTP file editor saves modified files with mode 666, replacing prior restrictions with world-readable and world-writable permissions. Exploitation requires local access and a privileged Wing FTP user to edit a sensitive file through HTTP; the resulting write access supports escalation to root.

The record

CVE
CVE-2020-8634
Published
Mar 6, 2020
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-281, T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Mar 6, 2020CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

7.2NIST NVDAV:L/AC:L/Au:N/C:C/I:C/A:C
7.8NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-281Improper Preservation of Permissions
T1068Exploitation for Privilege Escalation

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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