Cyber Resilience

CVE-2023-1671

RCE in Sophos Web Appliance ≤ 4.3.10.4

CISA KEVActive ExploitationEUVD ExploitedPublic PoCRCECommand Injection
Published
04 April 2023
Modified
27 October 2025
KEV Added
16 November 2023
Patch / advisory
View advisory
CVSS Score v3.1 9.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.99 100.0th percentile
Risk Priority 97 floored blend · peak EPSS

Summary

CVE-2023-1671 is a critical-severity Command Injection (CWE-77) vulnerability in Sophos Web Appliance. Its CVSS base score is 9.8 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Command and Scripting Interpreter (T1059); ranked in the top 0.0% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog; a public proof-of-concept is referenced.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2023-1671 is a pre-authentication command injection vulnerability in the warn-proceed handler of Sophos Web Appliance versions prior to 4.3.10.4. The flaw, tracked under CWE-77, permits unauthenticated remote attackers to execute arbitrary operating-system commands and carries a CVSS 3.1 base score of 9.8.

An attacker with network access can submit a crafted request to the affected handler and obtain code execution without credentials or user interaction, resulting in full compromise of the confidentiality, integrity, and availability of the appliance.

Sophos security advisory sophos-sa-20230404-swa-rce states that the issue is resolved in version 4.3.10.4 and urges customers to apply the update immediately. The vulnerability is also listed in CISA’s Known Exploited Vulnerabilities catalog, confirming observed in-the-wild exploitation. The associated EPSS score has remained consistently high, with a peak of 0.9691 and a current value of 0.9430.

OWASP Top 10 for Web (2025)

A05:2025 Injection

EU & UK References

Vulnerability Data

A pre-auth command injection vulnerability in the warn-proceed handler of Sophos Web Appliance older than version 4.3.10.4 allows execution of arbitrary code.

CWE(s)
CWE-77
KEV Date Added
16 November 2023

Related Threats

MITRE ATT&CK Enterprise Techniques

T1059 Command and Scripting Interpreter Execution
Adversaries may abuse command and script interpreters to execute commands, scripts, or binaries.
attack.mitre.org →
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
T1059.001 PowerShell Execution
Adversaries may abuse PowerShell commands and scripts for execution.
attack.mitre.org →
T1059.003 Windows Command Shell Execution
Adversaries may abuse the Windows command shell for execution.
attack.mitre.org →
T1059.004 Unix Shell Execution
Adversaries may abuse Unix shell commands and scripts for execution.
attack.mitre.org →
T1059.008 Network Device CLI Execution
Adversaries may abuse scripting or built-in command line interpreters (CLI) on network devices to execute malicious command and payloads.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-33336Same product: Sophos Web Appliance
CVE-2023-1389Shared CWE-77both on KEV
CVE-2012-1823Shared CWE-77both on KEV
CVE-2019-0541Shared CWE-77both on KEV
CVE-2005-2773Shared CWE-77both on KEV
CVE-2020-25079Shared CWE-77both on KEV
CVE-2020-25223Same vendor: Sophosboth on KEV
CVE-2022-40765Shared CWE-77both on KEV
CVE-2023-20118Shared CWE-77both on KEV
CVE-2024-3273Shared CWE-77both on KEV

Affected Assets

sophos
web appliance
≤ 4.3.10.4

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)

—

Validate
Prove the fix (OWASP ASVS)
  • V1.2.3
  • V1.2.5
  • V1.2.8
  • V1.2.9

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly require input validation and neutralization that prevent command injection.

DE.CM-09 partial match
prevents

Runtime monitoring of software and data can detect anomalous command execution resulting from injection.

ID.RA-01 partial match
prevents

Identifying recorded vulnerabilities enables remediation of command-injection flaws before exploitation.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.28 Secure coding mostly match
prevents

Secure coding standards require proper escaping and parameterization of commands, directly eliminating CWE-77.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing in development catches command-injection vulnerabilities before release.

A.8.25 Secure development life cycle partial match
prevents

Secure development life cycle mandates input validation and command construction practices that directly prevent command injection.

A.8.26 Application security requirements partial match
prevents

Application security requirements explicitly call for controls against injection flaws including command injection.

A.8.27 Secure system architecture and engineering principles partial match
prevents

Secure architecture principles reduce the attack surface but do not prescribe the specific neutralization techniques needed.

A.8.31 Separation of development, test and production environments none match
none

Environment separation limits the blast radius of an exploited command injection but does not prevent the flaw itself.

References