CVE-2021-41635Public exploitNetwork attack vector

Host compromise via SYSTEM-level service execution

Published Jun 24, 2022 · Updated Aug 4, 2024

Privilege amplification in MELAG FTP Server 2.2.0.4 allows remote attackers to gain SYSTEM-level host access through a compromised service. The Windows service installer registers the FTP server under NT AUTHORITY\SYSTEM rather than a restricted service account. Exposure requires the install-as-service option and a separately exploitable FTP flaw or misconfiguration; a compromise then inherits full host privileges.

CVSS severity8.8
High
EPSS probability2.14%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Privilege amplification in MELAG FTP Server 2.2.0.4 allows remote attackers to gain SYSTEM-level host access through a compromised service. The Windows service installer registers the FTP server under NT AUTHORITY\SYSTEM rather than a restricted service account. Exposure requires the install-as-service option and a separately exploitable FTP flaw or misconfiguration; a compromise then inherits full host privileges.

The record

CVE
CVE-2021-41635
Published
Jun 24, 2022
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-276, T1068
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 24, 2022CVE 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 vectornetwork
Required privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

8.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
9.0NIST NVDAV:N/AC:L/Au:S/C:C/I:C/A:C

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-276Incorrect Default 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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