What it is
CVE-2026-112353 is an unauthenticated vulnerability affecting GFI USA GFI KerioConnect. GFI KerioConnect (Kerio Connect) before 10.0.8 Patch 2 contains a stored cross-site scripting vulnerability in the Webmail...
Vulnerability report
Exploitation attempts observed in the wild
High confidence
Not in CISA KEV
CVE-2026-112353
GFI KerioConnect < 10.0.8p2 Stored XSS Cross-Site Scripting
GFI USA / GFI KerioConnect · affected before 10.0.8p2
- Severity
- CVSS 6.2 · Medium
- Confidence
- High
- Exploit status
- Exploitation attempts observed in the wild
- EPSS
- 0.2%
- First observed
- —
- Last observed
- —
Decision summary
What security teams need to know first
Direct answers before the deeper technical record.
Have exploitation attempts been observed?
Yes. Exploitation attempts have been reported for this vulnerability. Previdian lists it as a known exploited vulnerability. Also reported by third-party sources. Confidence is high.
Who is affected?
GFI USA / GFI KerioConnect affected before 10.0.8p2.
What should we do?
Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.
Overview
GFI KerioConnect < 10.0.8p2 Stored XSS Cross-Site Scripting
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.
Vendor
Product
Affected
Status
GFI USA, LLC
Affected
GFI KerioConnect
Before 10.0.8p2
Affected
- Published
- 27 Oct 2026
- Exploitation Attempts Reported
- 27 Oct 2026
- Attack vector
- Remote
- Complexity
- Low
- Privileges
- None
- User interaction
- —
CVE References
- CVE Record CVE.org · CVE Record https://www.cve.org/CVERecord?id=CVE-2026-112353
- Release Notes gfi.ai · Patch https://gfi.ai/resource/kerioconnect-product-releases/
- VulnCheck Advisory: GFI KerioConnect < 10.0.8p2 Stored XSS via SVG Attachment vulncheck.com · Third-Party Advisory https://www.vulncheck.com/advisories/gfi-kerioconnect-8p2-stored-xss-...
Exploitation evidence
Evidence of exploitation attempts
Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.
Exploitation attempts observed in the wild
CVE
A trusted third party reported exploitation attempts.
Known exploited vulnerability sources
Per-source evidence links for KEV attestations are available through the Previdian Pro API.
Learn about Pro API access| Source | Added |
|---|---|
| CVE First | 2026-10-27 16:30 UTC |
Detection
Operational artifacts and observed signals
Make the evidence actionable in scanner, SOC, and edge-control workflows.
Scanner coverage
No scanner integrations recorded yet.
Virtual patch status
No Previdian virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.
Learn about virtual patches →No detection artifacts or sensor request patterns are available for this CVE yet.
Check back as sensor telemetry and scanner integrations are updated.
Risk and context
Severity, weaknesses, and research context
CVSS v4.0
6.2
Medium
Potential damage if exploited. Separate from whether attackers are using it.
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
EPSS
0.2%
Estimated chance of exploitation in the next 30 days. Previdian's warning comes from evidence, not this score.
All CVSS Scores
CVSS v4.0
6.2
Medium
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
CVSS v3.1
8.2
High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N
Timeline
From disclosure to observed exploitation attempts
-
16:30 UTC
Added to Previdian KEV Feed
High-confidence, third-party report of exploitation attempts
-
16:10 UTC
CVE published
Vulnerability disclosed publicly
-
14:41 UTC
CVE ID reserved
Identifier reserved by the CNA
Pro API
Automate this intelligence
Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.
- Evidence confidence and provenance
- First-party sensor telemetry
- PoC and scanner references
- Affected versions and enrichment
- Automation-ready JSON delivery
GET /api/v2/pro/kevs/CVE-2026-112353
Sample API response{
"cve_id": "CVE-2026-112353",
"confidence": "High",
"cvss_score": 6.2,
"cvss_estimated": false,
"epss_score": 0.00243,
"exploit_status": {
"exploited_in_the_wild": true,
"active_exploitation_observed": false
},
"sensor_telemetry": { "attempts": 0, "sensors": 0 }
}