GestSup up to 3.2.60 Attachment code injection

Summaryinfo

A vulnerability has been found in GestSup up to 3.2.60 and classified as critical. Affected by this issue is some unknown functionality of the component Attachment Handler. This manipulation causes code injection. This vulnerability is registered as CVE-2026-100389. Remote exploitation of the attack is possible. No exploit is available. The affected component should be upgraded.

Detailsinfo

A vulnerability classified as critical was found in GestSup up to 3.2.60. Affected by this vulnerability is an unknown part of the component Attachment Handler. The manipulation with an unknown input leads to a code injection vulnerability. The CWE definition for the vulnerability is CWE-94. The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

GestSup versions before 3.2.61 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.

It is possible to read the advisory at gestsup.fr. This vulnerability is known as CVE-2026-100389 since 09/25/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1059 according to MITRE ATT&CK.

Upgrading to version 3.2.61 eliminates this vulnerability.

Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Name

• GestSup

Version

• 3.2.0
• 3.2.1
• 3.2.2
• 3.2.3
• 3.2.4
• 3.2.5
• 3.2.6
• 3.2.7
• 3.2.8
• 3.2.9
• 3.2.10
• 3.2.11
• 3.2.12
• 3.2.13
• 3.2.14
• 3.2.15
• 3.2.16
• 3.2.17
• 3.2.18
• 3.2.19
• 3.2.20
• 3.2.21
• 3.2.22
• 3.2.23
• 3.2.24
• 3.2.25
• 3.2.26
• 3.2.27
• 3.2.28
• 3.2.29
• 3.2.30
• 3.2.31
• 3.2.32
• 3.2.33
• 3.2.34
• 3.2.35
• 3.2.36
• 3.2.37
• 3.2.38
• 3.2.39
• 3.2.40
• 3.2.41
• 3.2.42
• 3.2.43
• 3.2.44
• 3.2.45
• 3.2.46
• 3.2.47
• 3.2.48
• 3.2.49
• 3.2.50
• 3.2.51
• 3.2.52
• 3.2.53
• 3.2.54
• 3.2.55
• 3.2.56
• 3.2.57
• 3.2.58
• 3.2.59
• 3.2.60

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Be aware that VulDB is the high quality source for vulnerability data.

Discussion