CVE-2006-1547
CVE-2006-1547 is a security flaw in Apache Struts 1, a framework for building Java web applications. Attackers can crash Apache Struts 1 or stop it working. The US Cybersecurity and Infrastructure Security Agency (CISA) added it to its catalog of flaws known to be used in attacks on 21 Jan 2022.[1]
Apache Struts 1 is business software or equipment. Most families won’t have it, but attackers break into it to get inside companies, and from there to what those companies hold about their customers, patients and staff.
Description
CISA calls it an actionForm denial-of-service in Apache Struts 1. In its words: “ActionForm in Apache Struts versions before 1.2.9 with BeanUtils 1.7 contains a vulnerability that allows for denial-of-service (DoS).”[1]
The CVE record adds: “ActionForm in Apache Software Foundation (ASF) Struts before 1.2.9 with BeanUtils 1.7 allows remote attackers to cause a denial of service via a multipart/form-data encoded form with a parameter name that references the public getMultipartRequestHandler method, which provides further access to elements in the CommonsMultipartRequestHandler implementation and BeanUtils.”[2]
The underlying weakness is CWE-749, in MITRE’s list of common software weaknesses.
It scores 7.5 out of 10 on the Common Vulnerability Scoring System, which rates it high, scored by NVD using CVSS 3.1.[2]
Affected versions
NVD’s record doesn’t list version ranges for it. CISA names the product as Apache Struts 1.
Most families won’t have Apache Struts 1; it’s for whoever looks after IT at work.
Exploitation
CISA added it to its catalog of known exploited vulnerabilities on 21 Jan 2022, 5,776 days after it was made public. CISA lists a flaw only when it has reliable evidence of it being exploited, and gave US federal agencies until 21 Jul 2022 to fix it.[1]
FIRST’s Exploit Prediction Scoring System, which estimates how likely a flaw is to be used in attacks in the next 30 days from what it sees across the internet, puts it at 55%. That’s in the top 1% of the flaws it scores.[3]
CISA assesses it as automatable: attackers can run it against many targets at once.
CISA doesn’t say who was attacked, or how.
Fix
CISA’s required action: “Apply updates per vendor instructions.”[1]
- Check whether you use it.Apache Struts 1 is business software or equipment, so most families won’t have it. If you run a business, or work from home on company equipment, ask whoever looks after your IT.
- Send this page to your IT person.Ask them to confirm it’s fixed, or not in use. CISA gave US government agencies until 21 Jul 2022 to fix it.
- If it can’t be fixed, take it offline.CISA’s advice when there’s no fix is to stop using the product, or take it off the internet, until there is one.
You can’t fix someone else’s server, but you can watch for what follows a break-in like this: a breach notice, a password reset you didn’t ask for, or a scam message that knows things it shouldn’t. HARD watches for those for you and your family.
Timeline
| Date | Event |
|---|---|
| The flaw is made public in the National Vulnerability Database, with a severity score of 7.5.[2] | |
| CISA adds it to its catalog of flaws known to be used in attacks.[1] | |
| CISA’s deadline for US government agencies to fix it.[1] | |
| FIRST puts the odds of it being used in attacks in the next 30 days at 55%.[3] |
See also
Other Apache Struts 1 flaws
- CVE-2017-9791: improper input validation ·
Other Apache flaws
- CVE-2016-3081, Apache Struts: command injection ·
- CVE-2026-34486, Apache Tomcat: missing encryption of sensitive data ·
- CVE-2026-34197, Apache ActiveMQ: improper input validation ·
- CVE-2024-38475, Apache HTTP Server: improper escaping of output ·
- CVE-2025-24813, Apache Tomcat: path equivalence ·
Similar flaws
- CVE-2018-19322, GIGABYTE products: code execution ·
- CVE-2021-36942, Microsoft Windows: local security authority (LSA) spoofing ·
Added the same day
- CVE-2021-35247, SolarWinds Serv-U: improper input validation ·
- CVE-2018-8453, Microsoft Win32k: privilege escalation ·
- CVE-2012-0391, Apache Struts 2: improper input validation ·
Every Apache flaw on CISA’s list · Everything added in January 2022
References
- ^ Cybersecurity and Infrastructure Security Agency. “Apache Struts 1 ActionForm Denial-of-Service Vulnerability”. Known Exploited Vulnerabilities Catalog, added 21 Jan 2022.
- ^ National Institute of Standards and Technology. “CVE-2006-1547 Detail”. National Vulnerability Database, published 30 Mar 2006.
- ^ FIRST. “Exploit Prediction Scoring System”. EPSS 0.546, percentile 99.0, 31 Oct 2026.
- CVE Program. “CVE-2006-1547”. The official CVE record.
This article is built from CISA’s catalog (version 2026.10.30), NVD’s record and FIRST’s scores, kept in HARD’s database and checked every morning. The plain English is HARD’s.