CVE-2021-25265Network attack vector

User-triggered remote code execution

Published Mar 22, 2021 · Updated Aug 3, 2024

Remote code execution in Sophos Connect Client 2.0 for Windows allows remote attackers to run arbitrary code through a malicious website. Sophos has not published the affected component or the operation that mishandles website-supplied content. Exploitation requires a Windows user to visit attacker-controlled web content; the resulting code runs on the endpoint.

CVSS severity8.8
High
EPSS probability1.85%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Remote code execution in Sophos Connect Client 2.0 for Windows allows remote attackers to run arbitrary code through a malicious website. Sophos has not published the affected component or the operation that mishandles website-supplied content. Exploitation requires a Windows user to visit attacker-controlled web content; the resulting code runs on the endpoint.

The record

CVE
CVE-2021-25265
Published
Mar 22, 2021
Updated
Aug 3, 2024
Vendor
Sophos
Product
Sophos Connect Client
Classifications
T1189, T1203
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 22, 2021CVE 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 <=2.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Sophos · Sophos Connect Clientversion=unspecified <=2.0

Published CVSS scores

6.8NVDAV:N/AC:M/Au:N/C:P/I:P/A:P
8.8NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/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.

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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1189Drive-by Compromise
T1203Exploitation for Client Execution

Public exploit references

No public exploit references are available in this record.

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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