What is CVE-2026-102374?

CVE-2026-102374 is a medium-severity vulnerability in Gestsup, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2026-09-29.

How severe is CVE-2026-102374?

Medium severity. CVSS v3 base score is 6.1 out of 10.

XSS in Gestsup

CVE-2026-102374

GestSup versions before 3.2.62 contain a stored cross-site scripting vulnerability in the IMAP OAuth connector that double-decodes MIME-encoded email subjects after HTML escaping. Unauthenticated attackers can send crafted emails to monitored mailboxes with nested MIME encoded-words to inject JavaScript that executes in technician sessions when viewing tickets.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2026-09-29 · last modified 2026-09-29.

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Gestsup

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

gestsup.fr/index.php (release-notes)
gestsup.fr/index.php (product)
gestsup.fr/index.php (patch)
www.vulncheck.com/advisories/gestsup-before-3.2.62-stored-xss-via-double-decode… (third-party-advisory)

Frequently asked questions

What is CVE-2026-102374?: CVE-2026-102374 is a medium-severity vulnerability in Gestsup, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2026-09-29.
How severe is CVE-2026-102374?: Medium severity. CVSS v3 base score is 6.1 out of 10.