CVE-2026-100389 json
GestSup before 3.2.62 Remote Code Execution via IMAP Attachment
published 2026-09-25 44 d ago modified 2026-09-30 39 d ago also EUVD-2026-87326
- cvss
- 8.1
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.6%
- EPSS 0.6% chance of exploitation in 30 days, percentile 47%
- public exploits
- 0
- none known
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.
Patch / fix
- GestSup GestSup 3.2.62
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 40 d ago
Exploit prediction
0.58% chance of exploitation in the next 30 days, higher than 47% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- blog.spiizn.xyz https://blog.spiizn.xyz/articles/remote-code-execution-turning-a-ticket-into-a-new-issue/ referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 9.2 | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N |
| CNA | 3.1 | 8.1 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H |
| CNA | 4.0 | 9.2 | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Affected products
- GestSup GestSup
Classification
- Weakness
-
- CWE-434 Unrestricted Upload of File with Dangerous Type
References
-
blog.spiizn.xyz
/articles/remote-code-execution-turning-a-ticket-into-a-new-issue/
technical-description, exploit
-
gestsup.fr
/index.php?page=changelog
release-notes
-
gestsup.fr
/index.php?page=download
product
-
vulncheck.com
/advisories/gestsup-before-3.2.61-remote-code-execution-via-imap-attachment
third-party-advisory
Sources
- CVE List CVE-2026-100389
- NVD CVE-2026-100389
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