{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-33523","assignerOrgId":"f0158376-9dc2-43b6-827c-5f631a4d8d09","state":"PUBLISHED","assignerShortName":"apache","dateReserved":"2026-03-20T17:29:39.696Z","datePublished":"2026-05-04T14:40:41.430Z","dateUpdated":"2026-05-04T17:32:49.282Z"},"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Apache HTTP Server","vendor":"Apache Software Foundation","versions":[{"lessThanOrEqual":"2.4.66","status":"affected","version":"2.4.0","versionType":"semver"}]}],"credits":[{"lang":"en","type":"finder","value":"Haruki Oyama (Waseda University)"},{"lang":"en","type":"finder","value":"Merih Mengisteab"},{"lang":"en","type":"finder","value":"Dawit Jeong"}],"descriptions":[{"lang":"en","supportingMedia":[{"base64":false,"type":"text/html","value":"<p>HTTP response splitting vulnerability in multiple Apache HTTP Server modules with untrusted or compromised backend servers.</p><p>This issue affects Apache HTTP Server: from through 2.4.66.</p><p>Users are recommended to upgrade to version 2.4.67, which fixes the issue.</p>"}],"value":"HTTP response splitting vulnerability in multiple Apache HTTP Server modules with untrusted or compromised backend servers.\n\nThis issue affects Apache HTTP Server: from through 2.4.66.\n\nUsers are recommended to upgrade to version 2.4.67, which fixes the issue."}],"metrics":[{"other":{"content":{"text":"low"},"type":"Textual description of severity"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-443","description":"CWE-443: HTTP response splitting","lang":"en","type":"CWE"}]}],"providerMetadata":{"orgId":"f0158376-9dc2-43b6-827c-5f631a4d8d09","shortName":"apache","dateUpdated":"2026-05-04T14:40:41.430Z"},"references":[{"tags":["vendor-advisory"],"url":"https://httpd.apache.org/security/vulnerabilities_24.html"}],"source":{"discovery":"UNKNOWN"},"timeline":[{"lang":"en","time":"2026-03-05T12:00:00.000Z","value":"reported"},{"lang":"eng","time":"2026-05-04T12:00:00.000Z","value":"2.4.67 released"},{"lang":"en","time":"2026-05-04T12:00:00.000Z","value":"fixed in 2.4.x by r1933360"}],"title":"Apache HTTP Server: multiple modules: HTTP response splitting forwarding malicious status line","x_generator":{"engine":"Vulnogram 0.2.0"}},"adp":[{"metrics":[{"cvssV3_1":{"scope":"UNCHANGED","version":"3.1","baseScore":6.5,"attackVector":"NETWORK","baseSeverity":"MEDIUM","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N","integrityImpact":"LOW","userInteraction":"NONE","attackComplexity":"LOW","availabilityImpact":"NONE","privilegesRequired":"NONE","confidentialityImpact":"LOW"}},{"other":{"type":"ssvc","content":{"timestamp":"2026-05-04T15:55:00.471385Z","id":"CVE-2026-33523","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-05-04T15:56:35.673Z"}},{"title":"CVE Program Container","references":[{"url":"http://www.openwall.com/lists/oss-security/2026/05/04/23"}],"providerMetadata":{"orgId":"af854a3a-2127-422b-91ae-364da2661108","shortName":"CVE","dateUpdated":"2026-05-04T17:32:49.282Z"}}]}}