OS Command Injection in Freepbx (CVE-2026-40520)
Summary
OS command injection in Freepbx (CVE-2026-40520). Successful exploitation can lead to full system takeover.
Original description
The description as published by the source.
FreePBX api module version 17.0.8 and prior contain a command injection vulnerability in the initiateGqlAPIProcess() function where GraphQL mutation input fields are passed directly to shell_exec() without sanitization or escaping. An authenticated user with a valid bearer token can send a GraphQL moduleOperations mutation with backtick-wrapped commands in the module field to execute arbitrary commands on the underlying host as the web server user.
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-2026-40520 has been found in Freepbx.
Successful exploitation can lead to full system takeover. CVSS score: 7.2/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Freepbx CVE-2026-40520" on the vendor's site.
CVE-2026-40520 (Freepbx) — CWE-78 / CVSS v3 7.2
Attack vector: remote (network-reachable) / 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.
OS command injection (CWE-78) exists in Freepbx.
Check the vendor advisory for the affected versions of Freepbx.
Severity: High (CVSS 7.2/10). Successful exploitation can lead to full system takeover.
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 'Freepbx' . 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 'Freepbx' . | 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
Freepbx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。
References
- advisory disclosure@vulncheck.com
- patch disclosure@vulncheck.com
- web disclosure@vulncheck.com
- web disclosure@vulncheck.com