Cross-Site Scripting (XSS) in FreeScout (CVE-2026-107393)
Summary
Cross-site scripting in FreeScout (CVE-2026-107393). Risk of unauthorized operations or information disclosure.
Original description
The description as published by the source.
FreeScout is a self-hosted help desk and shared mailbox. Prior to 1.8.235, when APP_CLOUDFLARE_IS_USED is enabled, FreeScout trusts an unvalidated CF-Connecting-IP header during failed login attempts and stores the spoofed value in the activity log. LogsMonitor inserts the value into an administrator alert email without HTML escaping, allowing injected HTML to execute when an administrator opens the email. This issue is fixed in version 1.8.235.
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-2026-107393 has been found in FreeScout.
Risk of unauthorized operations or information disclosure. CVSS score: 6.1/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "FreeScout CVE-2026-107393" on the vendor's site.
CVE-2026-107393 (FreeScout) — CWE-79 / CVSS v3 6.1
Attack vector: remote (network-reachable) / unauthenticated
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.
Cross-site scripting (XSS) (CWE-79) exists in FreeScout.
Check the vendor advisory for the affected versions of FreeScout.
Severity: Medium (CVSS 6.1/10). Risk of unauthorized operations or information disclosure.
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. Run grep -r 'FreeScout' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'FreeScout' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
FreeScoutを grep し、稼働しているサービス・バージョンを把握する。 -
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。