rust-openssl provides OpenSSL bindings for the Rust programming language. From 0.9.24 to before 0.10.78, the FFI trampolines behind SslContextBuilder::set_psk_client_callback, set_psk_server_callback, set_cookie_generate_cb, and set_stateless_cookie_generate_cb forwarded the user closure's returned usize directly to OpenSSL without checking it against the &mut [u8] that was handed to the closure. This can lead to buffer overflows and other unintended consequences. This vulnerability is fixed in 0.10.78.
https://github.com/rust-openssl/rust-openssl/security/advisories/GHSA-hppc-g8h3-xhp3
https://github.com/rust-openssl/rust-openssl/releases/tag/openssl-v0.10.78
https://github.com/rust-openssl/rust-openssl/pull/2607
https://github.com/rust-openssl/rust-openssl/commit/1d109020d98fff2fb2e45c39a373af3dff99b24c
Published: 2026-04-24
Updated: 2026-04-24
Base Score: 7.5
Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P
Severity: High
Base Score: 9.8
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Severity: Critical
Base Score: 8.3
Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:L/SC:N/SI:N/SA:N
Severity: High