Known exploited · Apache

CVE-2006-1547: Apache Struts 1 ActionForm Denial-of-Service Vulnerability

What it is

ActionForm in Apache Struts versions before 1.2.9 with BeanUtils 1.7 contains a vulnerability that allows for denial-of-service (DoS).

Added January 21, 2022Due July 21, 2022CISA KEV catalog 2026.10.01

Vendor
Apache
Product
Struts 1
Added to KEV
January 21, 2022
CISA due date
July 21, 2022
Ransomware use
Unknown
Weakness
Not mapped by CISA

What CISA requires

Apply updates per vendor instructions.

Forensic triage

No

What to do now

  1. Find every instance of Struts 1 you run, including the forgotten ones, and check its version against the vendor advisory.
  2. Apply the vendor's fix or mitigation, before July 21, 2022 if you are bound by CISA's deadline, sooner if it faces the internet.
  3. Assume it was tried against you already: look for signs of exploitation from the date it was added, not from the day you patched.

References

CVE-2006-1547 in the National Vulnerability Database

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Source: CISA Known Exploited Vulnerabilities Catalog (public domain), catalog version 2026.10.01.