GestSup versions before 3.2.61 contain a remote code execution vulnerability in the basic IMAP connector's attachment handling that fails to skip… (CVE-2026-100389)
GestSup versions before 3.2.61 have a remote code execution vulnerability in the basic IMAP connector's attachment handling. The vulnerability arises because the system fails to skip blocked file extensions, allowing unauthenticated attackers to send emails with PHP attachments to monitored mailboxes. These attachments are saved in a web-accessible directory and executed when accessed, leading to potential full system compromise.
AI Analysis
Technical Summary
CVE-2026-100389 describes a remote code execution vulnerability in GestSup's basic IMAP connector prior to version 3.2.61. The flaw is due to improper handling of email attachments where blocked file extensions, specifically PHP files, are not skipped. Attackers can exploit this by sending crafted emails with PHP attachments to monitored mailboxes. These attachments are stored in the web-accessible upload/ticket directory and executed upon access, enabling remote code execution without authentication.
Potential Impact
Successful exploitation allows unauthenticated remote attackers to execute arbitrary code on the affected system with high impact on confidentiality, integrity, and availability. This can lead to full system compromise, data theft, or service disruption.
Mitigation Recommendations
A fix is available in GestSup version 3.2.61. Users should upgrade to version 3.2.61 or later to remediate this vulnerability. No other mitigation guidance is provided in the vendor advisory.
GestSup versions before 3.2.61 contain a remote code execution vulnerability in the basic IMAP connector's attachment handling that fails to skip… (CVE-2026-100389)
Description
GestSup versions before 3.2.61 have a remote code execution vulnerability in the basic IMAP connector's attachment handling. The vulnerability arises because the system fails to skip blocked file extensions, allowing unauthenticated attackers to send emails with PHP attachments to monitored mailboxes. These attachments are saved in a web-accessible directory and executed when accessed, leading to potential full system compromise.
CVSS v3.1
Score 8.1high
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-100389 describes a remote code execution vulnerability in GestSup's basic IMAP connector prior to version 3.2.61. The flaw is due to improper handling of email attachments where blocked file extensions, specifically PHP files, are not skipped. Attackers can exploit this by sending crafted emails with PHP attachments to monitored mailboxes. These attachments are stored in the web-accessible upload/ticket directory and executed upon access, enabling remote code execution without authentication.
Potential Impact
Successful exploitation allows unauthenticated remote attackers to execute arbitrary code on the affected system with high impact on confidentiality, integrity, and availability. This can lead to full system compromise, data theft, or service disruption.
Mitigation Recommendations
A fix is available in GestSup version 3.2.61. Users should upgrade to version 3.2.61 or later to remediate this vulnerability. No other mitigation guidance is provided in the vendor advisory.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-3p62-2wp9-6rpj
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-100389"]
- Database Specific Severity
- CRITICAL
- Cvss Version
- 3.1
Threat ID: 6ab74f64f7a7c54106e14e48
Added to database: 09/26/2026, 04:51:48 UTC
Last enriched: 09/26/2026, 05:05:52 UTC
Last updated: 09/26/2026, 19:53:30 UTC
Views: 36
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