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Exploited in the wildServers & business softwareWork IT

CVE-2026-102489 Zammad GmbH Zammad: software flaw

In plain words: A mistake in the software that attackers have found a way to abuse. Depends on the product — see the description and the vendor advisory.

Confirmed exploited by CISA on · US federal patch deadline Oct 5, 2026

What to do

  1. Install Zammad GmbH's security update for Zammad. If no update exists, follow the vendor's workaround or stop using the product until one ships.
  2. Keep a list of every internet-facing server you run so nothing is forgotten.
  3. Patch anything in this catalog first, ahead of normal patch cycles.
  4. Put admin and file-transfer apps behind a VPN or single sign-on instead of the open internet.

Read Zammad GmbH's advisory ↗

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
Zammad GmbH Zammad Session Fixation Vulnerability
Product
Zammad GmbH Zammad
CISA description
Zammad GmbH Zammad contains a session fixation vulnerability that can lead to remote code execution as the zammad user. This vulnerability can be chained with CVE-2026-102490.
Type of flaw
Software flaw (CWE-384)
Confirmed exploited
Oct 2, 2026
US federal patch deadline
Oct 5, 2026

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Answering about CVE-2026-102489 ·

Questions about CVE-2026-102489

Is CVE-2026-102489 being exploited?

Yes. CISA added CVE-2026-102489 to its Known Exploited Vulnerabilities catalog on Oct 2, 2026, which means there is reliable evidence of real-world attacks.

How do I fix CVE-2026-102489?

Install Zammad GmbH's security update for Zammad. 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-2026-102489?

Only if you use Zammad GmbH Zammad. Aimed mostly at company systems — you are affected through the companies you use, not your own phone.

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