{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-46428", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-05-13T22:18:22.830Z", "datePublished": "2026-07-20T15:37:58.396Z", "dateUpdated": "2026-07-20T15:37:58.396Z"}, "containers": {"cna": {"title": "lettre has TLS hostname verification disabled when using Boring TLS backend", "problemTypes": [{"descriptions": [{"cweId": "CWE-295", "lang": "en", "description": "CWE-295: Improper Certificate Validation", "type": "CWE"}]}], "metrics": [{"cvssV4_0": {"attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "PRESENT", "privilegesRequired": "NONE", "userInteraction": "NONE", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "HIGH", "vulnAvailabilityImpact": "NONE", "subConfidentialityImpact": "LOW", "subIntegrityImpact": "LOW", "subAvailabilityImpact": "NONE", "baseScore": 9.1, "baseSeverity": "CRITICAL", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:L/SI:L/SA:N", "version": "4.0"}}], "references": [{"name": "https://github.com/lettre/lettre/security/advisories/GHSA-4pj9-g833-qx53", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/lettre/lettre/security/advisories/GHSA-4pj9-g833-qx53"}, {"name": "https://github.com/lettre/lettre/commit/f5efffc88360dbdbfcef80f465e42d5bce68ca35", "tags": ["x_refsource_MISC"], "url": "https://github.com/lettre/lettre/commit/f5efffc88360dbdbfcef80f465e42d5bce68ca35"}, {"name": "https://github.com/lettre/lettre/releases/tag/v0.11.22", "tags": ["x_refsource_MISC"], "url": "https://github.com/lettre/lettre/releases/tag/v0.11.22"}, {"name": "https://rustsec.org/advisories/RUSTSEC-2026-0141.html", "tags": ["x_refsource_MISC"], "url": "https://rustsec.org/advisories/RUSTSEC-2026-0141.html"}], "affected": [{"vendor": "lettre", "product": "lettre", "versions": [{"version": ">= 0.10.1, < 0.11.22", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-07-20T15:37:58.396Z"}, "descriptions": [{"lang": "en", "value": "lettre is a a mailer library for Rust. Starting in version 0.10.1 and prior to version 0.11.22, an inverted-boolean bug in lettre's `boring-tls` integration silently disables TLS hostname verification for callers using the default (strict) configuration. An on-path attacker presenting any chain-valid certificate for any domain can intercept SMTP submission, including PLAIN/LOGIN credentials and message contents, against any lettre user built with the `boring-tls` feature. Other TLS backends (`native-tls`, `rustls`) are unaffected. Version 0.11.22 patches the issue."}], "source": {"advisory": "GHSA-4pj9-g833-qx53", "discovery": "UNKNOWN"}}}}

{}

{}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0.10.1,0.11.22)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "lettre", "source": "cna", "vendor": "lettre"}, "product": "lettre", "vendor": "lettre"}], "created": "2026-07-21T00:15:03.306429+00:00", "updated": "2026-07-21T00:15:03.306457+00:00", "vendors": ["lettre", "lettre$PRODUCT$lettre"]}