25 September 2026
Reference: CVE-2024-45519
1. What is being reported?
The postjournal service in Zimbra Collaboration software has a vulnerability that sometimes lets attackers execute commands on the system without any authentication. This means someone could potentially take control or disrupt your email system remotely.
2. What this means in plain English
If your organisation uses the affected versions of Zimbra, hackers could exploit this flaw to access sensitive emails, change information, or disrupt your email service. This could lead to business email compromise, data loss, or downtime.
3. Could this affect a small business?
Small businesses, charities, or clubs using Zimbra Collaboration versions before the fixed patches may be at risk. If you do not use Zimbra or have updated to the latest patches, you are likely not affected.
4. What to do now
- Check if your organisation uses Zimbra Collaboration email software and identify the version.
- Ask your IT provider or software supplier if your version is affected by this vulnerability.
- Apply the latest security patches or updates provided by Zimbra immediately if you are using an affected version.
- Monitor your email system for unusual activity and ensure backups are up to date.
5. Ask your IT provider
Can you confirm if our Zimbra Collaboration email software is affected by CVE-2024-45519, and have the necessary security patches been applied to protect against this vulnerability?
6. Bottom line
If you use Zimbra email software, update it now to prevent hackers from taking control of your email system.
Information based on CISA KEV, NVD, and reputable security reporting including Rapid7.