{"id":"RUSTSEC-2026-0346","aliases":["GHSA-c8m5-c952-6cm4"],"title":"`Debug` impls for client session values expose TLS secrets","summary":"`Debug` impls for client session values expose TLS secrets","severity":"medium","cvss":4,"cvssVector":"CVSS:3.1/AV:L/AC:H/PR:H/UI:R/S:U/C:H/I:N/A:N","vendor":"rustls","product":"rustls","ecosystem":"rust","affected":["rustls >= 0.21.0, < 0.23.46"],"patched":["rustls 0.23.46"],"published":"2026-10-14","updated":"2026-10-14","sourceUpdated":"2026-10-14T13:30:02.480694744Z","source":"OSV","sourceUrl":"https://osv.dev/vulnerability/RUSTSEC-2026-0346","references":[{"url":"https://crates.io/crates/rustls"},{"url":"https://rustsec.org/advisories/RUSTSEC-2026-0346.html"},{"url":"https://github.com/rustls/rustls/pull/3299"}],"tags":["osv","rust"],"ingestedAt":"2026-10-15T11:47:08.229Z","slug":"RUSTSEC-2026-0346","body":"## Overview\n\nThe `Debug` implementations of `Tls12ClientSessionValue` and\n`Tls13ClientSessionValue` were derived, and so included the TLS 1.2 master\nsecret or TLS 1.3 resumption PSK in their output.\n\nCustom `ClientSessionStore` implementations that format these values with\n`Debug` (for example, when logging) could disclose these secrets to readers of\nthe logs. This conflicts with rustls's\n[key-material redaction policy](https://github.com/rustls/rustls/blob/99f2358cae2954837dbb866faf6727de75489ab9/SECURITY.md#boundary-public-api).\n\nOrdinary connection and built-in session cache `Debug` output is redacted and\nis not affected.\n\n## Affected packages\n\n- `rustls >= 0.21.0, < 0.23.46`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `rustls 0.23.46`","depth":"sunlit","depthScore":22,"depthScoreParts":{"impact":22,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}