CVE-2026-100389 GestSup before 3.2.62 Remote Code Execution via IMAP Attachment
Unauthenticated attackers can achieve remote code execution by sending emails with PHP attachments to monitored mailboxes in GestSup.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-100389?
CVE-2026-100389 is a critical vulnerability in GestSup, published on 25 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
GestSup versions before 3.2.62 contain a remote code execution vulnerability in the basic IMAP connector's attachment handling that fails to skip blocked file extensions. Unauthenticated attackers can send emails with PHP attachments to monitored mailboxes, which are written to the web-accessible upload/ticket directory and executed when accessed.
Weakness: CWE-434
Which versions are affected by CVE-2026-100389?
How do I fix CVE-2026-100389?
No fix has been published for CVE-2026-100389 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-100389 being exploited?
There is no known exploitation of CVE-2026-100389 in the wild and no public exploit code.
Sources
Also known as GHSA-3p62-2wp9-6rpj.