{"items":[{"id":"NVI-00015261","kind":"vulnerability","title":"lettre has TLS hostname verification disabled when using Boring TLS backend","revision":3,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected.","NVD lastModified does not establish freshness of every associated CPE record."],"lifecycle":"active","identifiers":["GHSA-4pj9-g833-qx53","CVE-2026-46428"],"plain_summary":"GitHub lists this reviewed advisory for lettre. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.","source_ids":["sr-156bf094dc1bdfbff902e20aff5c1104"],"action_type":"investigate","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null}],"schema_version":"1.1.0","source_metrics":[{"kind":"CVSS","as_of":"2026-07-23T17:58:34.990Z","value":"9.1 CRITICAL (4.0)","meaning":"security-advisories@github.com severity; no combined Null risk score.","source_id":"sr-6de711497eee1582d864dbbcdd79ea18"},{"kind":"EPSS","as_of":"2026-11-04T12:03:12.000Z","value":"0.319%","meaning":"FIRST EPSS model v2026.06.15; exploitation probability over 30 days, percentile 0.25033. Missing scores are unknown.","source_id":"sr-156bf094dc1bdfbff902e20aff5c1104"}],"why_it_matters":"Published affected context helps an owner decide what evidence to gather. This report has not examined your application.","related_sources":[{"id":"sr-4c2b453524adf41a5d89cc517ac967c5","url":"https://github.com/advisories/GHSA-4pj9-g833-qx53","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-4pj9-g833-qx53","publisher":"GitHub Advisory Database","observed_at":"2026-11-03T09:59:04.660Z"},{"id":"sr-6de711497eee1582d864dbbcdd79ea18","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-46428","basis":"official_catalog","notes":"This product uses data from the NVD API but is not endorsed or certified by the NVD.","title":"CVE-2026-46428","publisher":"NIST National Vulnerability Database","observed_at":"2026-11-08T01:47:36.551Z"},{"id":"sr-156bf094dc1bdfbff902e20aff5c1104","url":"https://www.first.org/epss/data.html","basis":"official_catalog","notes":"FIRST EPSS; probability of exploitation in the next 30 days, not local compromise. Dataset date/model retained; FIRST services terms apply.","title":"CVE-2026-46428","publisher":"FIRST EPSS","observed_at":"2026-11-04T17:58:50.328Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-4c2b453524adf41a5d89cc517ac967c5"],"technology":"lettre","known_exclusions":[],"conditions_summary":"### Summary\nAn inverted-boolean bug in lettre's `boring-tls` integration silently\ndisables TLS hostname verification for callers using the default (strict)\nconfiguration. An on-path attacker presenting any chain-valid certificate\nfor any domain can intercept SMTP submission, including PLAIN/LOGIN\ncredentials and message contents, against any lettre user built with the\n`boring-tls` feature. Other TLS backends (`native-tls`, `rustls`) are\nunaffected.\n\n### Details\nboring's `SslConnectorBuilder::set_verify_hostname(bool)` /\n`verify_hostname(bool)` API takes a *verify* flag — `true` means enforce\nhostname verification, `false` means skip it. (Boring docs:\nhttps://docs.rs/boring/latest/boring/ssl/struct.ConnectConfiguration.html#method.set_verify_hostname)\nlettre's `TlsParametersBuilder` exposes the opposite-named flag\n`accept_invalid_hostnames: bool` — `true` means *accept invalid* (skip\nverification), `false` means verify. lettre passes this flag directly to\nboring at both TLS-upgrade sites, inverting the semantics:\nsrc/transport/smtp/client/net.rs:202 (sync)\n    .verify_hostname(*accept_invalid_hostnames)\nsrc/transport/smtp/client/async_net.rs:377 (async)\n    config.set_verify_hostnam","public_affected_ranges":[">= 0.10.1, < 0.11.22"]}],"null_published_at":"2026-11-08T19:53:48.745Z","source_updated_at":"2026-07-28T14:29:11.000Z","source_disclosed_at":"2026-07-28T14:29:10.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"Source facts changed; compare the preserved prior revision.","null_first_observed_at":"2026-11-03T09:59:04.660Z"},{"id":"NVI-00015261","kind":"vulnerability","title":"lettre has TLS hostname verification disabled when using Boring TLS backend","revision":1,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-4pj9-g833-qx53","CVE-2026-46428"],"plain_summary":"GitHub lists this reviewed advisory for lettre. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.","source_ids":["sr-4c2b453524adf41a5d89cc517ac967c5"],"action_type":"investigate","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null}],"schema_version":"1.1.0","source_metrics":[],"why_it_matters":"Published affected context helps an owner decide what evidence to gather. This report has not examined your application.","related_sources":[{"id":"sr-4c2b453524adf41a5d89cc517ac967c5","url":"https://github.com/advisories/GHSA-4pj9-g833-qx53","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-4pj9-g833-qx53","publisher":"GitHub Advisory Database","observed_at":"2026-11-03T09:59:04.660Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-4c2b453524adf41a5d89cc517ac967c5"],"technology":"lettre","known_exclusions":[],"conditions_summary":"### Summary\nAn inverted-boolean bug in lettre's `boring-tls` integration silently\ndisables TLS hostname verification for callers using the default (strict)\nconfiguration. An on-path attacker presenting any chain-valid certificate\nfor any domain can intercept SMTP submission, including PLAIN/LOGIN\ncredentials and message contents, against any lettre user built with the\n`boring-tls` feature. Other TLS backends (`native-tls`, `rustls`) are\nunaffected.\n\n### Details\nboring's `SslConnectorBuilder::set_verify_hostname(bool)` /\n`verify_hostname(bool)` API takes a *verify* flag — `true` means enforce\nhostname verification, `false` means skip it. (Boring docs:\nhttps://docs.rs/boring/latest/boring/ssl/struct.ConnectConfiguration.html#method.set_verify_hostname)\nlettre's `TlsParametersBuilder` exposes the opposite-named flag\n`accept_invalid_hostnames: bool` — `true` means *accept invalid* (skip\nverification), `false` means verify. lettre passes this flag directly to\nboring at both TLS-upgrade sites, inverting the semantics:\nsrc/transport/smtp/client/net.rs:202 (sync)\n    .verify_hostname(*accept_invalid_hostnames)\nsrc/transport/smtp/client/async_net.rs:377 (async)\n    config.set_verify_hostnam","public_affected_ranges":[">= 0.10.1, < 0.11.22"]}],"null_published_at":"2026-11-03T10:03:26.565Z","source_updated_at":"2026-07-28T14:29:11.000Z","source_disclosed_at":"2026-07-28T14:29:10.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"First indexed by Null; source disclosure date is shown separately.","null_first_observed_at":"2026-11-03T09:59:04.660Z"}],"next_cursor":null,"snapshot_revision":"42594"}