CVE-2026-34197 Apache ActiveMQ: command or code injection
In plain words: The program treats text it receives as instructions instead of plain data. The attacker can run commands on the machine — often the whole device is taken over.
Confirmed exploited by CISA on · US federal patch deadline Apr 30, 2026
What to do
- Install Apache's security update for ActiveMQ. If no update exists, follow the vendor's workaround or stop using the product until one ships.
- Keep a list of every internet-facing server you run so nothing is forgotten.
- Patch anything in this catalog first, ahead of normal patch cycles.
- Put admin and file-transfer apps behind a VPN or single sign-on instead of the open internet.
Who is affected
Work IT. Aimed mostly at company systems — you are affected through the companies you use, not your own phone.
What's at risk: Mass data theft and ransomware: a single flaw in a file-transfer or email server has exposed thousands of organisations at once.
The details
- Official name
- Apache ActiveMQ Improper Input Validation Vulnerability
- Product
- Apache ActiveMQ
- CISA description
- Apache ActiveMQ contains an improper input validation vulnerability that allows for code injection.
- Type of flaw
- Command or code injection (CWE-20, CWE-94)
- Confirmed exploited
- Apr 16, 2026
- US federal patch deadline
- Apr 30, 2026
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Answering about CVE-2026-34197 ·
Questions about CVE-2026-34197
Is CVE-2026-34197 being exploited?
Yes. CISA added CVE-2026-34197 to its Known Exploited Vulnerabilities catalog on Apr 16, 2026, which means there is reliable evidence of real-world attacks.
How do I fix CVE-2026-34197?
Install Apache's security update for ActiveMQ. If no update exists, follow the vendor's workaround or stop using the product until one ships. Keep a list of every internet-facing server you run so nothing is forgotten.
Am I affected by CVE-2026-34197?
Only if you use Apache ActiveMQ. Aimed mostly at company systems — you are affected through the companies you use, not your own phone.