CVE-2023-1671Known exploitationPublic exploitNetwork attack vector

Unauthenticated code execution via warn-proceed injection

Published Apr 4, 2023 · Updated Oct 21, 2025

Command injection in Sophos Web Appliance before 4.3.10.4 allows remote attackers to execute arbitrary code through the warn-proceed handler. A public exploit places a Base64-encoded single-quote command sequence in the user_encoded field of a blocked-page continuation request. No account or user interaction is required, and successful exploitation grants arbitrary command execution on the appliance.

CVSS severity9.8
Critical
EPSS probability100.00%
Next 30 days · Sep 16, 2026
Known exploitationReported
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Command injection in Sophos Web Appliance before 4.3.10.4 allows remote attackers to execute arbitrary code through the warn-proceed handler. A public exploit places a Base64-encoded single-quote command sequence in the user_encoded field of a blocked-page continuation request. No account or user interaction is required, and successful exploitation grants arbitrary command execution on the appliance.

The record

CVE
CVE-2023-1671
Published
Apr 4, 2023
Updated
Oct 21, 2025
Vendor
Sophos
Product
Sophos Web Appliance
Classifications
CWE-77, T1190, T1059.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 4, 2023CVE publishedPublication date reported by the CVE source.
  2. Oct 21, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=unspecified <4.3.10.4

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Sophos · Sophos Web Applianceversion=unspecified <4.3.10.4

Published CVSS scores

9.8Sophos LimitedCVSS:3.1/AV:N/AC:L/PR:N/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.

Daily unique IPsShadowserver observations through Sep 16, 2026. Gaps indicate unavailable data.
Sep 10, 2026Sep 16, 2026
View daily counts
Reporting dayUnique IPs
Sep 10, 2026Unavailable
Sep 11, 2026Unavailable
Sep 12, 2026Unavailable
Sep 13, 2026Unavailable
Sep 14, 20261
Sep 15, 2026Unavailable
Sep 16, 2026Unavailable
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationReported
Public exploitPublished

Weakness, pattern, technique

CWE-77Improper Neutralization of Special Elements used in a Command ('Command Injection')
T1190Exploit Public-Facing Application
T1059.004Unix Shell

Public exploit references

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

Reported exploitation

Technologies

Your stack

See the directory against your own environment.

Your stack

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