# CVE-2026-102149 — Kiteworks Email Protection Gateway

> As of 2026-10-01, CVE-2026-102149 is a CRITICAL-severity vulnerability in Kiteworks Email Protection Gateway, CVSS v3.1 9.4, EPSS 0.2% (13.7th percentile). Threadlinqs Intelligence links 1 tracked threat campaign to CVE-2026-102149, most recently “Kiteworks 9.5.1 Patches 126 Vulnerabilities Including Critical Account Takeover in Core and Email Protection Gateway (CVE-2026-102147, CVE-2026-102149)”.

**Last updated:** 2026-10-01

## What is CVE-2026-102149?

Kiteworks Email Protection Gateway did not sufficiently restrict which account a certificate could be assigned to. This could allow an attacker to associate a certificate with another user's account, affecting the confidentiality and integrity of that account's encrypted mail and, where certificate-based login is enabled, potentially permitting unauthorized access to the account.

The record classifies CVE-2026-102149 under weakness class [CWE-306](https://intel.threadlinqs.com/cwe/CWE-306). Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs no prior authentication, needs no user interaction, and has high impact on confidentiality, integrity. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 25 days ago.

## Severity and exploitation probability

- **CVSS v3.1 base score:** 9.4 — CRITICAL (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L`)
- **EPSS (FIRST):** 0.2% probability of exploitation in the next 30 days, higher than 13.7% of all scored CVEs
- **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog
- **Threadlinqs priority:** 5.2/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- **Published:** 2026-09-30, last modified 2026-10-01

## Is CVE-2026-102149 being exploited?

It currently carries a trending score of 36 in the Threadlinqs vulnerability feed.

## Affected products and versions

- [Kiteworks](https://intel.threadlinqs.com/vendors/kiteworks): Email Protection Gateway

## How to fix CVE-2026-102149

No vendor patch reference has been recorded for CVE-2026-102149 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.

## Threat activity tracking CVE-2026-102149

1 tracked threat in the Threadlinqs corpus references CVE-2026-102149, either in the campaign’s CVE list or as an indicator on the campaign record.

- [Kiteworks 9.5.1 Patches 126 Vulnerabilities Including Critical Account Takeover in Core and Email Protection Gateway (CVE-2026-102147, CVE-2026-102149)](https://intel.threadlinqs.com/threat/TL-2026-2902) — CRITICAL · 2026-10-02

## Sources

Enriched from CVE.org, FIRST EPSS. Last verified by Threadlinqs on 2026-10-10.

**Third-party advisory**

- [raw.githubusercontent.com — third party advisory](https://raw.githubusercontent.com/cisagov/CSAF/develop/csaf_files/VA/white/2026/va-26-274-01.json)

**Other references**

- [github.com](https://github.com/kiteworks/security-advisories/security/advisories/GHSA-c9w5-4frw-7wqq)

Canonical: https://intel.threadlinqs.com/cve/CVE-2026-102149
Full detection coverage and IOCs for threats exploiting CVE-2026-102149 via the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp