CVE-2026-42498

import asyncio import websockets async def check_vuln(target_uri): # CVE-2026-42498 PoC Concept # Sending a WebSocket handshake with HTTP Auth headers # to check if headers are leaked to unexpected hosts. headers = { "Authorization": "Basic dGVzdF91c2VyOnRlc3RfcGFzcw==", # test_user:test_pass "User-Agent": "CVE-2026-42498-Scanner" } try: print(f"[*] Connecting to {target_uri}...") # In a vulnerable version, the Authorization header might be exposed # to an unexpected host during the handshake process. async with websockets.connect(target_uri, extra_headers=headers) as websocket: print("[+] Connection established.") print("[!] Monitor the network traffic or backend logs to verify header leakage.") await websocket.close() except Exception as e: print(f"[-] Error: {e}") if __name__ == "__main__": # Replace with actual vulnerable endpoint target = "ws://127.0.0.1:8080/ws/endpoint" asyncio.run(check_vuln(target))

{"cve": {"id": "CVE-2026-42498", "sourceIdentifier": "[email protected]", "published": "2026-05-12T16:16:17.800", "lastModified": "2026-05-14T18:51:59.217", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Exposure of HTTP Authentication Header to unexpected hosts during WebSocket authentication vulnerability in Apache Tomcat.\n\nThis issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.21, from 10.1.0-M1 through 10.1.54, from 9.0.2 through 9.0.117, from 8.5.24 through 8.5.100, from 7.0.83 through 7.0.109.\n\nUsers are recommended to upgrade to version 11.0.22, 10.1.55 or 9.0.118, which fix the issue."}], "metrics": {"cvssMetricV31": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L", "baseScore": 7.3, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "availabilityImpact": "LOW"}, "exploitabilityScore": 3.9, "impactScore": 3.4}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-200"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:apache:tomcat:*:*:*:*:*:*:*:*", "versionStartIncluding": "7.0.0", "versionEndIncluding": "7.0.109", "matchCriteriaId": "5BE0EC99-5BCD-4F7F-8124-4A1734B7BF6B"}, {"vulnerable": true, "criteria": "cpe:2.3:a:apache:tomcat:*:*:*:*:*:*:*:*", "versionStartIncluding": "8.5.0", "versionEndIncluding": "8.5.100", "matchCriteriaId": "FF43D0D7-FBF3-4D7A-84C4-47B65A75A524"}, {"vulnerable": true, "criteria": "cpe:2.3:a:apache:tomcat:*:*:*:*:*:*:*:*", "versionStartIncluding": "9.0.0", "versionEndExcluding": "9.0.118", "matchCriteriaId": "1E5A897C-91F4-449E-984C-7D693B137EED"}, {"vulnerable": true, "criteria": "cpe:2.3:a:apache:tomcat:*:*:*:*:*:*:*:*", "versionStartIncluding": "10.1.0", "versionEndExcluding": "10.1.55", "matchCriteriaId": "5F289287-8587-4BB3-B4AB-3B5CF4A7D27A"}, {"vulnerable": true, "criteria": "cpe:2.3:a:apache:tomcat:*:*:*:*:*:*:*:*", "versionStartIncluding": "11.0.0", "versionEndExcluding": "11.0.22", "matchCriteriaId": "03FB799D-A66F-4792-A0CF-16D67BB53F08"}]}]}], "references": [{"url": "https://lists.apache.org/thread/n61zwf75jrv09rz90j4jssncm244bwdb", "source": "[email protected]", "tags": ["Mailing List", "Vendor Advisory"]}, {"url": "http://www.openwall.com/lists/oss-security/2026/05/12/14", "source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Mailing List", "Third Party Advisory"]}]}}