{"cve":{"cve_id":"CVE-2026-75595","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":0.00277,"epss_percentile":0.18815,"epss_as_of":"2026-10-15","description":"Netty is an asynchronous, event-driven network application framework. Prior to 4.1.137.Fina and 4.2.17.Final, io.netty.handler.ssl.SslClientHelloHandler#decode checks the wrong offset before reading the four-byte TLS handshake header, so a ClientHello whose handshake header spans records can cause an IndexOutOfBoundsException and invoke select(ctx, null). This selects the default SslContext instead of the SNI-specific context. In deployments where per-SNI clientAuth=REQUIRE is the sole mutual TLS gate, the default SslContext uses clientAuth=NONE or clientAuth=OPTIONAL, and no application-layer certificate verification exists, an unauthenticated remote attacker can bypass the protected route's mutual TLS requirement. This issue is fixed in versions 4.1.137.Final and 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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":"H","value_label":"High"},{"metric":"A","name":"Availability","value":"N","value_label":"None"}]},"cvss_v4_decoded":{"version":"4.0","metrics":[{"metric":"AV","name":"Attack Vector","value":"N","value_label":"Network"},{"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":"N","value_label":"None"},{"metric":"VC","name":"Confidentiality (Vulnerable System)","value":"H","value_label":"High"},{"metric":"VI","name":"Integrity (Vulnerable System)","value":"H","value_label":"High"},{"metric":"VA","name":"Availability (Vulnerable System)","value":"N","value_label":"None"},{"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":"netty","vendor_name":"netty","product_slug":"netty","product_name":"netty","version_start":"< 4.1.137.Final","version_start_inclusive":true,"version_end":"< 4.1.137.Final","version_end_inclusive":true,"cpe23_uri":"cve5:netty:netty:< 4.1.137.Final:< 4.1.137.Final"},{"vendor_slug":"netty","vendor_name":"netty","product_slug":"netty","product_name":"netty","version_start":">= 4.2.0.Final, < 4.2.17.Final","version_start_inclusive":true,"version_end":">= 4.2.0.Final, < 4.2.17.Final","version_end_inclusive":true,"cpe23_uri":"cve5:netty:netty:>= 4.2.0.Final, < 4.2.17.Final:>= 4.2.0.Final, < 4.2.17.Final"},{"vendor_slug":"netty","vendor_name":"netty","product_slug":"netty","product_name":"netty","version_start":null,"version_start_inclusive":null,"version_end":"4.1.137","version_end_inclusive":false,"cpe23_uri":"cpe:2.3:a:netty:netty:*:*:*:*:*:*:*:*"}],"exploit_refs":[],"news":[],"references":[{"url":"https://github.com/netty/netty/security/advisories/GHSA-c4c3-7fpv-j4q5","source_type":"VENDOR_ADVISORY","tags":["advisory"]},{"url":"https://github.com/netty/netty/pull/17213","source_type":"PATCH","tags":["patch"]},{"url":"https://github.com/netty/netty/pull/17217","source_type":"PATCH","tags":["patch"]},{"url":"https://github.com/netty/netty/commit/1b5abc6443b63726c72cdd285af2feb7ddbb8ff7","source_type":"PATCH","tags":["patch"]},{"url":"https://github.com/netty/netty/commit/9e0519239108a69b7e9bbc5e9182ee139a0d7961","source_type":"PATCH","tags":["patch"]},{"url":"https://github.com/netty/netty/releases/tag/netty-4.1.137.Final","source_type":"PATCH","tags":["patch"]},{"url":"https://github.com/netty/netty/releases/tag/netty-4.2.17.Final","source_type":"PATCH","tags":["patch"]}],"timeline":[{"type":"published","at":"2026-08-19T21:00:27.627000Z","label":"CVE 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