rust-openssl: Deriver::derive and PkeyCtxRef::derive can overflow short buffers on OpenSSL 1.1.1
`Deriver::derive` (and `PkeyCtxRef::derive`) sets `len = buf.len()` and passes it as the in/out length to `EVP_PKEY_derive`, relying on OpenSSL to honor it. On OpenSSL 1.1.x, X25519, X448, DH and HKDF-extract ignore the incoming `*keylen`, unconditionally writing the full shared secret (32/56/prime-size bytes). A caller passing a short slice gets a heap/stack overflow from safe code. OpenSSL 3.x providers do check, so this only impacts older OpenSSL.
describes (1)
Related CVEs.
| ID | severity | exploitable | ||
|---|---|---|---|---|
| CVE-2026-41676US | high7.5 | — | ||
rust-openssl provides OpenSSL bindings for the Rust programming language. From 0.9.27 to before 0.10.78, Deriver::derive (and PkeyCtxRef::derive) sets len = buf.len() and passes i… | ||||
references
External citations — patches, advisories, analysis.
- https://github.com/rust-openssl/rust-opensslPACKAGE
- https://github.com/rust-openssl/rust-openssl/commit/09b425e5f59a2466d806e71a83a9a449c914c596WEB
- https://github.com/rust-openssl/rust-openssl/pull/2606WEB
- https://github.com/rust-openssl/rust-openssl/releases/tag/openssl-v0.10.78WEB
- https://github.com/rust-openssl/rust-openssl/security/advisories/GHSA-pqf5-4pqq-29f5WEB
- https://nvd.nist.gov/vuln/detail/CVE-2026-41676ADVISORY
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