CVE-2021-36806

Severity: medium (CVSS 6.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2023-11-30 · updated 2026-06-17
Weakness: CWE-79

Description

A reflected XSS vulnerability allows an open redirect when the victim clicks a malicious link to an error page on Sophos Email Appliance older than version 4.5.3.4.

Affected products

Sophos Email Appliance: before 4.5.3.4 — fixed in 4.5.3.4

How to fix

Upgrade to a fixed version: Sophos Email Appliance 4.5.3.4. Check the vendor advisory for mitigations.

References

https://community.sophos.com/email-appliance/b/blog/posts/sophos-email-appliance-version-4-5-3-4-released
https://community.sophos.com/email-appliance/b/blog/posts/sophos-email-appliance-version-4-5-3-4-released

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