{"id":"CVE-2016-4975","url":"https://www.cyber-defence.io/tools/cve/CVE-2016-4975","generatedAt":"2026-11-05T03:39:19.818Z","title":"Possible CRLF injection allowing HTTP response splitting attacks for sites which use mod_userdir.","description":"Possible CRLF injection allowing HTTP response splitting attacks for sites which use mod_userdir. This issue was mitigated by changes made in 2.4.25 and 2.2.32 which prohibit CR or LF injection into the \"Location\" or other outbound header key or value. Fixed in Apache HTTP Server 2.4.25 (Affected 2.4.1-2.4.23). Fixed in Apache HTTP Server 2.2.32 (Affected 2.2.0-2.2.31).","published":"2018-08-14T12:29:00.000Z","lastModified":"2026-06-17T00:48:32.000Z","status":"Modified","sourceIdentifier":"security@apache.org","cvss":{"version":"3.0","score":6.1,"severity":"MEDIUM","vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"},"cwe":["CWE-93"],"affected":["apache/http server"],"epss":{"score":0.19798,"percentile":0.97418,"date":"2026-11-04","history":[{"date":"2026-09-21","score":0.24709,"percentile":0.97836},{"date":"2026-09-22","score":0.19798,"percentile":0.9729}]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"urgent","text":"EPSS puts the probability of exploitation in the next 30 days at 19.8%, higher than 97% of all known CVEs. Patch or mitigate before the next change window."},"changes":[],"references":[{"url":"http://www.securityfocus.com/bid/105093","tags":["Third Party Advisory","VDB Entry"],"source":"security@apache.org"},{"url":"https://httpd.apache.org/security/vulnerabilities_22.html#CVE-2016-4975","tags":["Vendor Advisory"],"source":"security@apache.org"},{"url":"https://httpd.apache.org/security/vulnerabilities_24.html#CVE-2016-4975","tags":["Vendor 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Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://support.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbux03908en_us","source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2016-4975","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}