CVE-2026-100389 (GCVE-0-2026-100389)
Vulnerability from cvelistv5 – Published: 2026-09-25 20:13 – Updated: 2026-09-30 11:15
VLAI
EPSS
VEX
Title
GestSup before 3.2.62 Remote Code Execution via IMAP Attachment
Summary
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.
Severity
8.1 (High)
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-29 18:20 UTC
CWE
- CWE-434 - Unrestricted Upload of File with Dangerous Type
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://gestsup.fr/index.php?page=changelog | release-notes |
| https://gestsup.fr/index.php?page=download | product |
| https://www.vulncheck.com/advisories/gestsup-befo… | third-party-advisory |
| https://blog.spiizn.xyz/articles/remote-code-exec… | technical-descriptionexploit |
Impacted products
Date Public
2026-08-24 00:00
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| Author | Source | Type | Date | Other |
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