{"cve":{"cve_id":"CVE-2026-42257","is_kev":false,"kev_date_added":null,"kev_vendor_project":null,"kev_product":null,"kev_vulnerability_name":null,"kev_short_description":null,"kev_required_action":null,"kev_due_date":null,"kev_known_ransomware":null,"kev_notes":null,"kev_cwes":null,"epss_score":0.00429,"epss_percentile":0.34199,"epss_as_of":"2026-06-23","description":"Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Prior to versions 0.4.24, 0.5.14, and 0.6.4, several Net::IMAP commands accept a raw string argument that is sent to the server without validation or escaping. If this string is derived from user-controlled input, it may contain contain CRLF sequences, which an attacker can use to inject arbitrary IMAP commands. This issue has been patched in versions 0.4.24, 0.5.14, and 0.6.4.","published_at":"2026-05-09T19:39:48.398000Z","last_modified_at":null,"cvss_v3_score":null,"cvss_v3_vector":null,"cvss_v3_severity":null,"cvss_v4_score":5.8,"cvss_v4_vector":"CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:P/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N","cvss_v4_severity":"MEDIUM","ssvc_decision":null,"ssvc_exploitation":null,"ssvc_automatable":null,"ssvc_technical_impact":null,"cwes":["CWE-93","CWE-77"],"nvd_references":["https://github.com/ruby/net-imap/security/advisories/GHSA-hm49-wcqc-g2xg","https://github.com/ruby/net-imap/releases/tag/v0.4.24","https://github.com/ruby/net-imap/releases/tag/v0.5.14","https://github.com/ruby/net-imap/releases/tag/v0.6.4"],"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":"2026-06-28T23:30:18.882139Z"},"effective_severity":"MEDIUM","badges":[],"impact_analysis":[],"cvss_v3_decoded":{"version":null,"metrics":[]},"cvss_v4_decoded":{"version":"4.0","metrics":[{"metric":"AV","name":"Attack Vector","value":"L","value_label":"Local"},{"metric":"AC","name":"Attack Complexity","value":"L","value_label":"Low"},{"metric":"AT","name":"Attack Requirements","value":"P","value_label":"Present"},{"metric":"PR","name":"Privileges Required","value":"N","value_label":"None"},{"metric":"UI","name":"User Interaction","value":"P","value_label":"Passive"},{"metric":"VC","name":"Confidentiality (Vulnerable System)","value":"N","value_label":"None"},{"metric":"VI","name":"Integrity (Vulnerable System)","value":"H","value_label":"High"},{"metric":"VA","name":"Availability (Vulnerable System)","value":"L","value_label":"Low"},{"metric":"SC","name":"Confidentiality (Subsequent System)","value":"N","value_label":"None"},{"metric":"SI","name":"Integrity (Subsequent System)","value":"N","value_label":"None"},{"metric":"SA","name":"Availability (Subsequent System)","value":"N","value_label":"None"}]},"affected":[{"vendor_slug":"ruby","vendor_name":"ruby","product_slug":"net-imap","product_name":"net-imap","version_start":"< 0.4.24","version_start_inclusive":true,"version_end":"< 0.4.24","version_end_inclusive":true,"cpe23_uri":"cve5:ruby:net-imap:< 0.4.24:< 0.4.24"},{"vendor_slug":"ruby","vendor_name":"ruby","product_slug":"net-imap","product_name":"net-imap","version_start":">= 0.5.0, < 0.5.14","version_start_inclusive":true,"version_end":">= 0.5.0, < 0.5.14","version_end_inclusive":true,"cpe23_uri":"cve5:ruby:net-imap:>= 0.5.0, < 0.5.14:>= 0.5.0, < 0.5.14"},{"vendor_slug":"ruby","vendor_name":"ruby","product_slug":"net-imap","product_name":"net-imap","version_start":">= 0.6.0, < 0.6.4","version_start_inclusive":true,"version_end":">= 0.6.0, < 0.6.4","version_end_inclusive":true,"cpe23_uri":"cve5:ruby:net-imap:>= 0.6.0, < 0.6.4:>= 0.6.0, < 0.6.4"}],"exploit_refs":[],"news":[],"references":[{"url":"https://github.com/ruby/net-imap/security/advisories/GHSA-hm49-wcqc-g2xg","source_type":"VENDOR_ADVISORY","tags":["advisory"]},{"url":"https://github.com/ruby/net-imap/releases/tag/v0.4.24","source_type":"PATCH","tags":["patch"]},{"url":"https://github.com/ruby/net-imap/releases/tag/v0.5.14","source_type":"PATCH","tags":["patch"]},{"url":"https://github.com/ruby/net-imap/releases/tag/v0.6.4","source_type":"PATCH","tags":["patch"]}],"timeline":[{"type":"published","at":"2026-05-09T19:39:48.398000Z","label":"CVE published","source":null},{"type":"cvss_changed","at":"2026-06-28T17:54:07.258310Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:54:07.258310Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:54:07.258310Z","label":"CVSS score revised","source":"cvelistv5"}]}