SSRF (Server-Side Request Forgery) in Kiteworks Email Protection Gateway (CVE-2026-102103)
Summary
SSRF in Kiteworks Email Protection Gateway (CVE-2026-102103). Confidential information can be exposed externally.
Original description
The description as published by the source.
Kiteworks Email Protection Gateway before version 9.5.0 is vulnerable to Server-Side Request Forgery (SSRF). A server-side request forgery (SSRF) weakness in Kiteworks Email Protection Gateway could allow a remote, unauthenticated attacker to induce the gateway to issue crafted requests to internal or otherwise unintended network destinations. The requests are triggered while the gateway retrieves a certificate revocation list in an inbound message. Depending on the services reachable from the gateway, this could disclose sensitive internal information or disrupt gateway operation.
Source: NIST National Vulnerability Database NVD
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-102103 has been found in Kiteworks Email Protection Gateway.
Confidential information can be exposed externally. CVSS score: 9.1/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Kiteworks Email Protection Gateway CVE-2026-102103" on the vendor's site.
CVE-2026-102103 (Kiteworks Email Protection Gateway) — CWE-918 / CVSS v3 9.1
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
SSRF (CWE-918) exists in Kiteworks Email Protection Gateway.
Check the vendor advisory for the affected versions of Kiteworks Email Protection Gateway.
Severity: Critical (CVSS 9.1/10). Confidential information can be exposed externally.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで Kiteworks Email Protection Gateway を使っているサービスとバージョンを洗い出す。
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2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
References
- patch github.com
- web raw.githubusercontent.com