{"cve":{"cve_id":"CVE-2021-41773","is_kev":true,"kev_date_added":"2021-11-03","kev_vendor_project":"Apache","kev_product":"HTTP Server","kev_vulnerability_name":"Apache HTTP Server Path Traversal Vulnerability","kev_short_description":"Apache HTTP Server contains a path traversal vulnerability that allows an attacker to perform remote code execution if files outside directories configured by Alias-like directives are not under default �require all denied� or if CGI scripts are enabled. The original patch issued under this CVE ID is insufficient, please review remediation information under CVE-2021-42013.","kev_required_action":"Apply updates per vendor instructions.","kev_due_date":"2021-11-17","kev_known_ransomware":true,"kev_notes":"https://nvd.nist.gov/vuln/detail/CVE-2021-41773","kev_cwes":["CWE-22"],"epss_score":0.99992,"epss_percentile":0.99985,"epss_as_of":"2026-06-23","description":"A flaw was found in a change made to path normalization in Apache HTTP Server 2.4.49. An attacker could use a path traversal attack to map URLs to files outside the directories configured by Alias-like directives. If files outside of these directories are not protected by the usual default configuration \"require all denied\", these requests can succeed. If CGI scripts are also enabled for these aliased pathes, this could allow for remote code execution. This issue is known to be exploited in the wild. This issue only affects Apache 2.4.49 and not earlier versions. The fix in Apache HTTP Server 2.4.50 was found to be incomplete, see CVE-2021-42013.","published_at":"2021-10-05T08:40:12Z","last_modified_at":null,"cvss_v3_score":7.5,"cvss_v3_vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","cvss_v3_severity":"HIGH","cvss_v4_score":null,"cvss_v4_vector":null,"cvss_v4_severity":null,"ssvc_decision":null,"ssvc_exploitation":"active","ssvc_automatable":true,"ssvc_technical_impact":"total","cwes":["CWE-22"],"nvd_references":["https://httpd.apache.org/security/vulnerabilities_24.html","https://lists.apache.org/thread.html/r6abf5f2ba6f1aa8b1030f95367aaf17660c4e4c78cb2338aee18982f%40%3Cusers.httpd.apache.org%3E","https://lists.apache.org/thread.html/r98d704ed4377ed889d40479db79ed1ee2f43b2ebdd79ce84b042df45%40%3Cannounce.apache.org%3E","http://www.openwall.com/lists/oss-security/2021/10/05/2","http://www.openwall.com/lists/oss-security/2021/10/07/1","https://lists.apache.org/thread.html/r7c795cd45a3384d4d27e57618a215b0ed19cb6ca8eb070061ad5d837%40%3Cannounce.apache.org%3E","https://lists.apache.org/thread.html/rb5b0e46f179f60b0c70204656bc52fcb558e961cb4d06a971e9e3efb%40%3Cusers.httpd.apache.org%3E","http://www.openwall.com/lists/oss-security/2021/10/07/6","https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-apache-httpd-pathtrv-LAzg68cZ","http://www.openwall.com/lists/oss-security/2021/10/08/1","https://lists.apache.org/thread.html/r17a4c6ce9aff662efd9459e9d1850ab4a611cb23392fc68264c72cb3%40%3Ccvs.httpd.apache.org%3E","http://www.openwall.com/lists/oss-security/2021/10/08/2","http://www.openwall.com/lists/oss-security/2021/10/08/3","http://www.openwall.com/lists/oss-security/2021/10/08/4","http://www.openwall.com/lists/oss-security/2021/10/08/6","http://www.openwall.com/lists/oss-security/2021/10/08/5","http://www.openwall.com/lists/oss-security/2021/10/09/1","http://packetstormsecurity.com/files/164418/Apache-HTTP-Server-2.4.49-Path-Traversal.html","http://packetstormsecurity.com/files/164418/Apache-HTTP-Server-2.4.49-Path-Traversal-Remote-Code-Execution.html","http://www.openwall.com/lists/oss-security/2021/10/11/4","https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RMIIEFINL6FUIOPD2A3M5XC6DH45Y3CC/","https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WS5RVHOIIRECG65ZBTZY7IEJVWQSQPG3/","http://www.openwall.com/lists/oss-security/2021/10/15/3","http://www.openwall.com/lists/oss-security/2021/10/16/1","https://www.oracle.com/security-alerts/cpujan2022.html","https://security.netapp.com/advisory/ntap-20211029-0009/","http://packetstormsecurity.com/files/164629/Apache-2.4.49-2.4.50-Traversal-Remote-Code-Execution.html","http://packetstormsecurity.com/files/164941/Apache-HTTP-Server-2.4.50-Remote-Code-Execution.html","https://security.gentoo.org/glsa/202208-20"],"vuln_status":null,"trending_score":0.6099856,"is_trending":false,"has_trended":false,"trended_number_one":false,"trending_peak_score":null,"trending_peak_rank":null,"started_trending_at":null,"trended_number_one_at":null,"summary_generated":null,"summary_generated_at":null,"summary_model":null,"created_at":"2026-06-24T00:09:31.350578Z","updated_at":"2026-06-29T02:30:27.550645Z"},"effective_severity":"HIGH","badges":["kev","ransomware","poc","epss"],"impact_analysis":[],"cvss_v3_decoded":{"version":"3.1","metrics":[{"metric":"AV","name":"Attack Vector","value":"N","value_label":"Network"},{"metric":"AC","name":"Attack Complexity","value":"L","value_label":"Low"},{"metric":"PR","name":"Privileges Required","value":"N","value_label":"None"},{"metric":"UI","name":"User Interaction","value":"N","value_label":"None"},{"metric":"S","name":"Scope","value":"U","value_label":"Unchanged"},{"metric":"C","name":"Confidentiality","value":"H","value_label":"High"},{"metric":"I","name":"Integrity","value":"N","value_label":"None"},{"metric":"A","name":"Availability","value":"N","value_label":"None"}]},"cvss_v4_decoded":{"version":null,"metrics":[]},"affected":[{"vendor_slug":"apache-software-foundation","vendor_name":"Apache Software Foundation","product_slug":"apache-http-server","product_name":"Apache HTTP Server","version_start":"Apache HTTP Server 2.4 2.4.49","version_start_inclusive":true,"version_end":"Apache HTTP Server 2.4 2.4.49","version_end_inclusive":true,"cpe23_uri":"cve5:apache-software-foundation:apache-http-server:Apache HTTP Server 2.4 2.4.49:Apache HTTP Server 2.4 2.4.49"}],"exploit_refs":[{"source":"nuclei","kind":"nuclei","url":"https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2021/CVE-2021-41773.yaml","title":"Apache 2.4.49 - Path Traversal and Remote Code 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