Description
GFI KerioConnect (Kerio Connect) before 10.0.8 Patch 2 contains a stored cross-site scripting vulnerability in the Webmail component that allows a remote attacker to run JavaScript in a victim's authenticated Webmail session by uploading a crafted SVG email attachment that bypasses sanitization of event-handler attributes. Attackers can exploit the temporary-download endpoint's insufficient Content-Security-Policy sandbox to execute scripts when the attachment is opened, enabling theft of the victim's credentials and mailbox contents. Proofpoint Threat Research has observed exploitation in the wild as a credential and mailbox stealer.
References2
Metrics
- CVSS 3.1
-
8.2
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N - CVSS 4.0
-
6.2
MEDIUM
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:H/SI:L/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 - EPSS — exploit probability
- 0% percentile: 16 · as of 5 November 2026
- CWE
- CWE-79CWE-83
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