CVE-2022-1040

An authentication bypass vulnerability in the User Portal and Webadmin allows a remote attacker to execute code in Sophos Firewall version v18.5 MR3 and older.

CVSS: 9.8Criticalscored by the publisher (CNA)
Exploited in the wild: Yes, in CISA KEV since 31 Mar 2022CISA deadline for US federal agencies: 21 Apr 2022public exploit code
EPSS: 99.8%chance of exploitation in the next 30 daystop 0.1% of scored CVEsFIRST score of 11 Nov 2026
Fix: Patch availablesee the advisories in the references
Published: 25 Mar 2022analysed here 12 Nov 2026

Do first. Apply updates per vendor instructions. (CISA's required action for this KEV entry)

Summary

Triage

Exploitable: At runtime
Attack vector: network
Can a WAF block it?: Partly. See why

The summary, impact and action text on this page are written by our AI analysis pipeline, or taken from the NVD description when a CVE was imported from NVD. They are not the vendor's wording: check them against the sources. A longer AI executive summary and technical analysis are generated for signed-in accounts on the Max plan.

Affected products

Product	Affected versions	Vendor says fixed in
Sophos Sophos Firewall	<= 18.5 MR3Vendor says fixed in: not stated	Not stated by the vendor

As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.

Products named in our analysis

sophos:sfos

Fix and mitigation

WAF and other mitigations

Can a WAF block it? Partly. The bug can be reached over the network, so generic WAF rules may stop some attacks. Its weakness type is unknown, so we cannot be more precise.

Also consider: patch

Based on the weakness type only; no CVE-specific evidence yet. We check Cloudflare, AWS, Google Cloud Armor and Azure; for Akamai, Imperva, Fastly, F5, ask your vendor.

Remediation steps (AI-written)

Step-by-step remediation is generated for accounts on the Max plan, for CVEs that match a technology in their stack. Add this technology to your stack to see the fix checklist.

Exploitation evidence

CISA KEV catalog: Listed since 31 Mar 2022.
CISA due date: 21 Apr 2022, the remediation deadline for US federal agencies
CISA required action: Apply updates per vendor instructions.
Public exploit code: Yes: 1 on Exploit-DB · 7 GitHub proofs of concept · 1 Nuclei template
CISA SSVC: exploitation active, automatable yes, technical impact totalAssessed by CISA 29 Jan 2025 (SSVC 2.0.3). Exploitation is none, poc (public proof of concept) or active.

Exploit-DB

Sophos XG115w Firewall 17.0.10 MR-10 - Authentication Bypasswebapps, 2 Sept 2022

Nuclei

Sophos Firewall <=18.5 MR3 - Remote Code Executiondetection template, critical

GitHub proofs of concept

and 3 more repositories

Listed so you can judge urgency, not as a recommendation to run anything. GitHub “proofs of concept” are unvetted: some are fake or carry malware. Exploit-DB marks the entries its staff verified.

Timeline

25 Mar 2022Published
31 Mar 2022Added to CISA KEV (exploited in the wild)5 days later
21 Apr 2022CISA remediation due date (US federal agencies)21 days later
6 May 2022First public exploit or proof of concept15 days later
29 Jan 2025CISA SSVC assessment: exploitation active1,000 days (about 3 years) later
21 Oct 2025CVE record last updated265 days (about 9 months) later
12 Nov 2026Analysed by vulneraibility.com387 days (about 1 year) later

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Metric	Value	What it means
Attack vector	NetworkReachable over the internet or any routable network.	Reachable over the internet or any routable network.
Attack complexity	LowRepeatable attack, no special conditions.	Repeatable attack, no special conditions.
Privileges required	NoneThe attacker needs no prior access.	The attacker needs no prior access.
User interaction	NoneNo victim action needed.	No victim action needed.
Scope	UnchangedImpact stays within the vulnerable component.	Impact stays within the vulnerable component.
Confidentiality	HighTotal data disclosure possible.	Total data disclosure possible.
Integrity	HighComplete modification possible.	Complete modification possible.
Availability	HighFull outage possible.	Full outage possible.

Common questions

Is CVE-2022-1040 being exploited?

Yes. CVE-2022-1040 appears in CISA's Known Exploited Vulnerabilities catalog, which means exploitation in the wild has been confirmed and reported. Treat it as active rather than theoretical, and patch it ahead of higher-scoring vulnerabilities that carry no exploitation evidence.

How severe is CVE-2022-1040?

CVE-2022-1040 is rated Critical with a CVSS score of 9.8. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.

Is there a patch for CVE-2022-1040?

Yes. A fix has been recorded for CVE-2022-1040. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.

What does CVE-2022-1040 affect?

CVE-2022-1040 affects sophos:sfos. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.

Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.

References

NVD CVE.org CVE Details Source

4 references in the CVE record, grouped by the tags the record gives them.

Where the data on this page comes from

CVE List (CVE.org): description, affected versions, references; CVE Terms of Use
NVD: CVSS and CPE data
CISA KEV catalog: exploitation, date added, due date
CISA Vulnrichment (ADP): SSVC decision points
FIRST EPSS: exploit probability and percentile
Exploit-DB: published exploits
Nuclei templates: detection templates
PoC-in-GitHub: GitHub repositories that claim a proof of concept

Summary, impact and triage tags: written by our AI analysis pipeline from the sources above. Check them against the sources.

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