CVE-2021-26630

Arbitrary file execution via unvalidated ActiveX path

Published May 19, 2022 · Updated Aug 3, 2024

Improper input validation in affected HANDY Groupware Windows releases allows attackers to execute arbitrary files through ActiveX. The HandySoft HShell FileStream Class passes a user-supplied download or execution path to its function without validating the argument. A user must visit a crafted page; affected branches end at 1.7.4.6, 2.0.3.6, and 4.0.1.7, and execution occurs in that user's context.

CVSS severity7.8
High
EPSS probability0.76%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in affected HANDY Groupware Windows releases allows attackers to execute arbitrary files through ActiveX. The HandySoft HShell FileStream Class passes a user-supplied download or execution path to its function without validating the argument. A user must visit a crafted page; affected branches end at 1.7.4.6, 2.0.3.6, and 4.0.1.7, and execution occurs in that user's context.

The record

CVE
CVE-2021-26630
Published
May 19, 2022
Updated
Aug 3, 2024
Vendor
Handysoft
Product
HANDY Groupware
Classifications
CWE-20, T1204
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 19, 2022CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 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?

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

  1. Affected versionversion=unspecified <=1.7.4.6
  2. Affected versionversion=unspecified <=2.0.3.6
  3. Affected versionversion=unspecified <=4.0.1.7

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Handysoft · HANDY Groupwareversion=unspecified <=1.7.4.6; version=unspecified <=2.0.3.6; version=unspecified <=4.0.1.7

Published CVSS scores

7.8KrCERT/CCCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
9.8NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
7.5NVDAV:N/AC:L/Au:N/C:P/I:P/A:P

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)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-20Improper Input Validation
T1204User Execution

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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