{"answers":{"affected":"3 open source packages ship an affected version, including lettre.","exploited":"It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-46428 exists.","fix":"Upgrade lettre to 0.11.22 or later.","what":"CVE-2026-46428 is a critical vulnerability in lettre, published on 20 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-46428 and fix it if it is affected.\n\nWhat it is: CVE-2026-46428 is a critical vulnerability in lettre, published on 20 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.\nExploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-46428 exists.\n\nAffected packages and fixed versions:\n- lettre (crates.io): affected from 0.10.1; fixed in 0.11.22\n- lettre (crates.io): affected from 0.10.1; fixed in 0.11.22\n- lettre (crates.io): affected from 0.10.1; fixed in 0.11.22\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2026-46428/ (Markdown: https://insights.sbomify.com/CVE-2026-46428/index.md)","id":"CVE-2026-46428","markdown":"https://insights.sbomify.com/CVE-2026-46428/index.md","name":"CVE-2026-46428","record":{"aliases":["GHSA-4pj9-g833-qx53","RUSTSEC-2026-0141"],"analysis":{"component_type":"library","fix_type":"patch","impacts":["data_read","account_takeover"],"network_reachable":"yes","non_default_config":false,"product_category":"Rust mailer library","requires_auth":"none","summary":"An attacker can intercept SMTP traffic and steal credentials because TLS hostname verification is disabled in the Boring TLS backend.","user_interaction":"not_required","vuln_class":"security_feature_bypass"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[],"cvss":{"score":9.1,"severity":"critical","source":"cna","vector":"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"},"cwes":[{"id":"CWE-295","name":"Improper Certificate Validation"}],"description":"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.","ecosystems":["crates.io"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"weaponised"},"has_fix":true,"headline":"lettre has TLS hostname verification disabled when using Boring TLS backend","id":"CVE-2026-46428","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"crates.io","product":null,"products":[],"type":"security_feature_bypass","year":"2026"},"n_packages":3,"n_references":4,"next":{"headline":"Algernon: Auto-refresh SSE event server binds to all interfaces by default on Linux/macOS","id":"CVE-2026-46430"},"packages":[{"ecosystem":"crates.io","fixed":["0.11.22"],"introduced":["0.10.1"],"last_affected":[],"package":"lettre","purl":null,"source":"GHSA-4pj9-g833-qx53"},{"ecosystem":"crates.io","fixed":["0.11.22"],"introduced":["0.10.1"],"last_affected":[],"package":"lettre","purl":"pkg:cargo/lettre","source":"GHSA-4pj9-g833-qx53"},{"ecosystem":"crates.io","fixed":["0.11.22"],"introduced":["0.10.1"],"last_affected":[],"package":"lettre","purl":"pkg:cargo/lettre","source":"RUSTSEC-2026-0141"}],"prev":{"headline":"Budibase: Snowflake private key returned unmasked from datasource API to BASIC users","id":"CVE-2026-46427"},"products":["lettre"],"published":"2026-07-20","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"GitHub Advisory Database","prefix":"GHSA"},{"class":"open","licence":"CC0 1.0","name":"RustSec","prefix":"RUSTSEC"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"poc","technical_impact":"total"},"state":"PUBLISHED","updated":"2026-07-21","vendors":["lettre"]},"summary":"An attacker can intercept SMTP traffic and steal credentials because TLS hostname verification is disabled in the Boring TLS backend.","url":"https://insights.sbomify.com/CVE-2026-46428/"}