CVE-2021-47791Public exploit

Application crash via malformed connection inputs

Published Jan 15, 2026 · Updated Jan 15, 2026

Denial of service in SmartFTP Client 10.0.2909.0 allows local users to crash the application through crafted connection input. The New Connection interface fails to reject a 425-character path beginning with two slashes, edits after an unreachable FTPS host returns an error, or input entered after connection history is cleared. Each trigger requires interaction with the Windows client interface and terminates only the client process; no data access or modification is reported.

CVSS severity4.6
Medium
EPSS probability0.53%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Denial of service in SmartFTP Client 10.0.2909.0 allows local users to crash the application through crafted connection input. The New Connection interface fails to reject a 425-character path beginning with two slashes, edits after an unreachable FTPS host returns an error, or input entered after connection history is cleared. Each trigger requires interaction with the Windows client interface and terminates only the client process; no data access or modification is reported.

The record

CVE
CVE-2021-47791
Published
Jan 15, 2026
Updated
Jan 15, 2026
Vendor
SmartSoft Ltd
Product
SmartFTP Client
Classifications
CWE-770, T1499.004
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 15, 2026CVE publishedPublication date reported by the CVE source.
  2. Jan 15, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=10.0.2909.0 (32 and 64 bit)

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

SmartSoft Ltd · SmartFTP Clientversion=10.0.2909.0 (32 and 64 bit)

Published CVSS scores

4.6VulnCheckCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
7.5VulnCheckCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-770Allocation of Resources Without Limits or Throttling
T1499.004Endpoint Denial of Service: Application or System Exploitation

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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