{"cve":{"cve_id":"CVE-2023-49105","is_kev":true,"kev_date_added":"2026-08-27","kev_vendor_project":"ownCloud","kev_product":"ownCloud","kev_vulnerability_name":"ownCloud Improper Authentication Vulnerability","kev_short_description":"ownCloud contains an improper authentication vulnerability that allows an attacker to access, modify, or delete any file without authentication if the username of a victim is known, and the victim has no signing-key configured.","kev_required_action":"Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.","kev_due_date":"2026-08-30","kev_known_ransomware":false,"kev_notes":"https://owncloud.org/security ; https://owncloud.com/security-advisories/webdav-api-authentication-bypass-using-pre-signed-urls/ ; BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk ; Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk ; https://nvd.nist.gov/vuln/detail/CVE-2023-49105","kev_cwes":["CWE-287"],"epss_score":0.11074,"epss_percentile":0.95589,"epss_as_of":"2026-08-26","description":"An issue was discovered in ownCloud owncloud/core before 10.13.1. An attacker can access, modify, or delete any file without authentication if the username of a victim is known, and the victim has no signing-key configured. This occurs because pre-signed URLs can be accepted even when no signing-key is configured for the owner of the files. The earliest affected version is 10.6.0.","published_at":"2023-11-21T00:00:00Z","last_modified_at":null,"cvss_v3_score":9.8,"cvss_v3_vector":"CVSS:3.1/AC:L/AV:N/A:H/C:H/I:H/PR:N/S:U/UI:N","cvss_v3_severity":"CRITICAL","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-287"],"nvd_references":["https://owncloud.org/security","https://owncloud.com/security-advisories/webdav-api-authentication-bypass-using-pre-signed-urls/"],"vuln_status":null,"trending_score":null,"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":"2026-06-24T00:09:39.878444Z","updated_at":"2026-08-27T23:40:11.369738Z"},"effective_severity":"CRITICAL","badges":["kev","poc"],"impact_analysis":[],"cvss_v3_decoded":{"version":"3.1","metrics":[{"metric":"AC","name":"Attack Complexity","value":"L","value_label":"Low"},{"metric":"AV","name":"Attack Vector","value":"N","value_label":"Network"},{"metric":"A","name":"Availability","value":"H","value_label":"High"},{"metric":"C","name":"Confidentiality","value":"H","value_label":"High"},{"metric":"I","name":"Integrity","value":"H","value_label":"High"},{"metric":"PR","name":"Privileges Required","value":"N","value_label":"None"},{"metric":"S","name":"Scope","value":"U","value_label":"Unchanged"},{"metric":"UI","name":"User Interaction","value":"N","value_label":"None"}]},"cvss_v4_decoded":{"version":null,"metrics":[]},"affected":[],"exploit_refs":[{"source":"nuclei","kind":"nuclei","url":"https://github.com/projectdiscovery/nuclei-templates/blob/main/code/cves/2023/CVE-2023-49105.yaml","title":"OwnCloud - WebDAV API Authentication Bypass","author":"ChristianPoeschl,FlorianDewald,usdAG","disclosed_at":null}],"news":[],"references":[{"url":"https://owncloud.org/security","source_type":"MISC","tags":[]},{"url":"https://owncloud.com/security-advisories/webdav-api-authentication-bypass-using-pre-signed-urls/","source_type":"VENDOR_ADVISORY","tags":["advisory"]}],"timeline":[{"type":"published","at":"2023-11-21T00:00:00Z","label":"CVE published","source":null},{"type":"poc_available","at":"2026-06-24T00:29:48.638073Z","label":"Public PoC available","source":"nuclei"},{"type":"cvss_changed","at":"2026-06-28T17:30:41.329074Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:30:41.329074Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:30:41.329074Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"ssvc_changed","at":"2026-06-29T01:40:39.262006Z","label":"SSVC decision revised","source":"vulnrichment"},{"type":"ssvc_changed","at":"2026-06-29T01:40:39.262006Z","label":"SSVC decision revised","source":"vulnrichment"},{"type":"ssvc_changed","at":"2026-06-29T01:40:39.262006Z","label":"SSVC decision revised","source":"vulnrichment"},{"type":"cisa_reported","at":"2026-08-27T00:00:00Z","label":"Added to CISA KEV catalog","source":"kev"},{"type":"ssvc_changed","at":"2026-08-27T23:40:11.369738Z","label":"SSVC decision revised","source":"vulnrichment"}]}