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.

  • Published Sep 29, 2026
  • CVSS 5.3 medium
  • 0.2% chance of exploitation in the next 30 days (EPSS)
  • A fix is available

Affected software

CVE-2026-102374 at the National Vulnerability Database