Security Digest · Vulnerability record · Known exploited
CVE-2023-1671: Sophos Web Appliance Command Injection Vulnerability
Exploited in the wild (CISA KEV). 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.
CISA KEV · added 2023-11-16 CVSS 9.8 Critical EPSS 100.0% · p100.0
Should you act?
Exploited: patch now if you run it
CISA has confirmed exploitation in the wild. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.
- Yes, if you run Sophos Web Appliance. CISA added this CVE to its Known Exploited Vulnerabilities catalog on 2023-11-16, which means there is reliable evidence of exploitation in the wild. US federal agencies must remediate by 2023-12-07; treat that as the outer limit, not the target.
- EPSS 100.0%, percentile 100.0: FIRST’s model estimates a 100.0% chance of exploitation activity in the next 30 days, higher than 100.0% of all scored CVEs (very high). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
What it is
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.
CISA’s summary
Sophos Web Appliance contains a command injection vulnerability in the warn-proceed handler that allows for remote code execution.
Weakness type: CWE-77.
Product: Sophos Web Appliance · Assigned by: Sophos · Published: 2023-04-04
Affected and fixed versions
| Vendor | Product | Affected versions (per CVE record) |
|---|---|---|
| Sophos | Sophos Web Appliance | unspecified < 4.3.10.4 |
Severity scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| Sophos | 3.1 | 9.8 Critical | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
- Attack vector: network (remotely reachable)
- Attack complexity: low
- Privileges required: none (no login)
- User interaction: none
- Scope: unchanged
CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.
Exploitation and urgency
- CISA KEV: added 2023-11-16; federal due date 2023-12-07. Known ransomware use: Unknown.
- CISA required action: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
- CISA SSVC assessment: exploitation active, automatable yes, technical impact total.
- FIRST EPSS (model of 2026-10-21): 100.00% probability of exploitation activity in the next 30 days; percentile 100.0.
Timeline
- — CVE record published by Sophos
- — Added to CISA’s Known Exploited Vulnerabilities catalog
- — CISA remediation deadline for US federal agencies
- — CVE record last updated
Sources and references
Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.
Vendor and project advisories, patches
- Listed in CISA KEV notes (sophos.com) sophos.com
Vulnerability records
- CVE.org record CVE-2023-1671 cve.org
- NVD entry CVE-2023-1671 nvd.nist.gov
Government
Other references from the CVE record and advisory
- packetstormsecurity.com packetstormsecurity.com
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