{"cve":{"cve_id":"CVE-2021-40438","is_kev":true,"kev_date_added":"2021-12-01","kev_vendor_project":"Apache","kev_product":"Apache","kev_vulnerability_name":"Apache HTTP Server-Side Request Forgery (SSRF)","kev_short_description":"A crafted request uri-path can cause mod_proxy to forward the request to an origin server choosen by the remote user. This issue affects Apache HTTP Server 2.4.48 and earlier.","kev_required_action":"Apply updates per vendor instructions.","kev_due_date":"2021-12-15","kev_known_ransomware":false,"kev_notes":"https://nvd.nist.gov/vuln/detail/CVE-2021-40438","kev_cwes":["CWE-918"],"epss_score":0.99999,"epss_percentile":0.99997,"epss_as_of":"2026-06-23","description":"A crafted request uri-path can cause mod_proxy to forward the request to an origin server choosen by the remote user. 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Server-Side Request Forgery","author":"pdteam","disclosed_at":null}],"news":[],"references":[{"url":"https://httpd.apache.org/security/vulnerabilities_24.html","source_type":"MISC","tags":[]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SPBR6WUYBJNACHKE65SPL7TJOHX7RHWD/","source_type":"MAILING_LIST","tags":["mailing-list"]},{"url":"https://lists.apache.org/thread.html/r82838efc5fa6fc4c73986399c9b71573589f78b31846aff5bd9b1697%40%3Cusers.httpd.apache.org%3E","source_type":"MAILING_LIST","tags":["mailing-list"]},{"url":"https://lists.apache.org/thread.html/r82c077663f9759c7df5a6656f925b3ee4f55fcd33c889ba7cd687029%40%3Cusers.httpd.apache.org%3E","source_type":"MAILING_LIST","tags":["mailing-list"]},{"url":"https://lists.apache.org/thread.html/r3925e167d5eb1c75def3750c155d753064e1d34a143028bb32910432%40%3Cusers.httpd.apache.org%3E","source_type":"MAILING_LIST","tags":["mailing-list"]},{"url":"https://lists.apache.org/thread.html/r61fdbfc26ab170f4e6492ef3bd5197c20b862ce156e9d5a54d4b899c%40%3Cusers.httpd.apache.org%3E","source_type":"MAILING_LIST","tags":["mailing-list"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZNCYSR3BXT36FFF4XTCPL3HDQK4VP45R/","source_type":"MAILING_LIST","tags":["mailing-list"]},{"url":"https://lists.debian.org/debian-lts-announce/2021/10/msg00001.html","source_type":"MAILING_LIST","tags":["mailing-list"]},{"url":"https://lists.apache.org/thread.html/r2eb200ac1340f69aa22af61ab34780c531d110437910cb9c0ece3b37%40%3Cbugs.httpd.apache.org%3E","source_type":"MAILING_LIST","tags":["mailing-list"]},{"url":"https://www.debian.org/security/2021/dsa-4982","source_type":"VENDOR_ADVISORY","tags":["advisory"]},{"url":"https://lists.apache.org/thread.html/r210807d0bb55f4aa6fbe1512be6bcc4dacd64e84940429fba329967a%40%3Cusers.httpd.apache.org%3E","source_type":"MAILING_LIST","tags":["mailing-list"]},{"url":"https://lists.apache.org/thread.html/rf6954e60b1c8e480678ce3d02f61b8a788997785652e9557a3265c00%40%3Cusers.httpd.apache.org%3E","source_type":"MAILING_LIST","tags":["mailing-list"]},{"url":"https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-apache-httpd-2.4.49-VWL69sWQ","source_type":"VENDOR_ADVISORY","tags":["advisory"]},{"url":"https://www.oracle.com/security-alerts/cpujan2022.html","source_type":"VENDOR_ADVISORY","tags":["advisory"]},{"url":"https://www.tenable.com/security/tns-2021-17","source_type":"MISC","tags":[]},{"url":"https://security.netapp.com/advisory/ntap-20211008-0004/","source_type":"MISC","tags":[]},{"url":"https://www.oracle.com/security-alerts/cpuapr2022.html","source_type":"VENDOR_ADVISORY","tags":["advisory"]},{"url":"https://cert-portal.siemens.com/productcert/pdf/ssa-685781.pdf","source_type":"MISC","tags":[]},{"url":"https://security.gentoo.org/glsa/202208-20","source_type":"MISC","tags":[]}],"timeline":[{"type":"published","at":"2021-09-16T14:40:23Z","label":"CVE published","source":null},{"type":"cisa_reported","at":"2021-12-01T00:00:00Z","label":"Added to CISA KEV catalog","source":"kev"},{"type":"poc_available","at":"2026-06-24T00:29:48.638073Z","label":"Public PoC available","source":"nuclei"},{"type":"ssvc_changed","at":"2026-06-24T00:31:45.921816Z","label":"SSVC decision revised","source":"vulnrichment"},{"type":"ssvc_changed","at":"2026-06-24T00:31:45.921816Z","label":"SSVC decision revised","source":"vulnrichment"},{"type":"ssvc_changed","at":"2026-06-24T00:31:45.921816Z","label":"SSVC decision revised","source":"vulnrichment"},{"type":"cvss_changed","at":"2026-06-24T00:31:45.921816Z","label":"CVSS score revised","source":"vulnrichment"},{"type":"cvss_changed","at":"2026-06-24T00:31:45.921816Z","label":"CVSS score revised","source":"vulnrichment"},{"type":"cvss_changed","at":"2026-06-24T00:31:45.921816Z","label":"CVSS score revised","source":"vulnrichment"},{"type":"started_trending","at":"2026-06-29T02:30:27.366045Z","label":"Started trending","source":null}]}