CVE•Published 2026-07-20•Modified 2026-07-23•0 articles on news•5 live references•NVD data

CVE-2026-46428

Vulnerability data via NVD (ingested)

CVSS v3.1

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EPSS percentile

Exploit Prediction Scoring System · top 91% of all CVEs

Weaknesses (CWE)

CWE-295Improper 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.

Timeline

Published 2026-07-20

Modified 2026-07-23

External references

NVD MITRE Exploit-DB trickest/cve VulnCheck

Search for exposed instances

Shodan + Censys queries derived from NVD's CPE data. The vuln tag catches assets Shodan has explicitly linked to this CVE; the product / banner fingerprints find exposed instances even when the vuln tag was never applied (which is common).

Shodan · vuln tag0 hosts

vuln:CVE-2026-46428

Hosts Shodan has explicitly fingerprinted as vulnerable.

More intel sources (5)

Shodan report

vuln:CVE-2026-46428

Country / ASN / product breakdown for the vuln query.

Censys

vulnerabilities.cve_id: CVE-2026-46428

Censys host search filtered to this CVE id.

grep.app

CVE-2026-46428