CVE-2021-25267
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedMultiple XSS vulnerabilities in Webadmin allow for privilege escalation from admin to super-admin in Sophos Firewall older than version 19.0 GA.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · moderate confidenceMultiple cross-site scripting (XSS) vulnerabilities in the Webadmin interface of Sophos Firewall allow an authenticated admin user to escalate privileges to super-admin by tricking a super-admin user into clicking a malicious link or visiting a crafted page.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data< 19.0CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- High
- User interaction
- Required
- Scope
- Changed
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:H/I:H/A:H
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
-
Check Sophos Firewall firmware versionAccess the Webadmin interface and navigate to System > Administration > System > System Information, or use the command 'version' in the console to display the firmware version.Affected if The displayed firmware version is any version prior to 19.0 (e.g., 18.x, 17.x, etc.)
-
Confirm Webadmin interface is enabledNavigate to System > Administration > Webadmin in the Webadmin interface and verify the service status, or check via console with 'webadmin --status' command.Affected if Webadmin interface is enabled and accessible (this is the default configuration)
A user is affected if their Sophos Firewall is running firmware version older than 19.0 and the Webadmin interface is enabled, allowing XSS-based privilege escalation from admin to super-admin.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scoped19.0
Upgrade Sophos Firewall to version 19.0 GA or later to address these XSS vulnerabilities and prevent privilege escalation.
Sophos Firewall version 19.0 GA
- 1. Backup the current Sophos Firewall configuration
- 2. Download Sophos Firewall version 19.0 GA or later from the official Sophos download portal
- 3. Access the firewall Webadmin interface
- 4. Navigate to System > Firmware or the appropriate firmware update section
- 5. Upload and apply the firmware version 19.0 GA
- 6. After reboot, verify the upgrade was successful by checking the firmware version in Webadmin
- 7. Confirm that the XSS vulnerability is resolved by logging in and verifying normal admin and super-admin functionality
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation3.0 h
- Implementation4.0 h
- Testing6.0 h
- Review / QA3.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $4,416.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-25267 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2021-25267 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.
A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.
- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
- No spam, self-promotion, credentials, or personal data