CVE-2021-25267Network attack vector

Admin-to-super-admin escalation via Webadmin XSS

Published May 5, 2022 · Updated Aug 3, 2024

Cross-site scripting in Sophos Firewall Webadmin before 19.0 GA allows remote authenticated users to escalate from admin to super-admin. Sophos has not published the affected Webadmin inputs or the output-handling error that permits script injection. Exploitation requires an authenticated administrator and user interaction in Webadmin, after which the attacker gains super-admin control over the firewall.

CVSS severity6.8
Medium
EPSS probability1.08%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cross-site scripting in Sophos Firewall Webadmin before 19.0 GA allows remote authenticated users to escalate from admin to super-admin. Sophos has not published the affected Webadmin inputs or the output-handling error that permits script injection. Exploitation requires an authenticated administrator and user interaction in Webadmin, after which the attacker gains super-admin control over the firewall.

The record

CVE
CVE-2021-25267
Published
May 5, 2022
Updated
Aug 3, 2024
Vendor
Sophos
Product
Sophos Firewall
Classifications
CWE-79, T1059.007
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. May 5, 2022CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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

  1. Affected versionversion=unspecified <19.0 GA

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

Sophos · Sophos Firewallversion=unspecified <19.0 GA

Published CVSS scores

8.4NVDCVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:H/I:H/A:H
6.8SophosCVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:H/I:H/A:H
8.5NVDAV:N/AC:M/Au:S/C:C/I:C/A:C

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 IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1059.007Command and Scripting Interpreter: JavaScript

Public exploit references

No public exploit references are available in this record.

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

Technologies

Your stack

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Your stack

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