CVE-2026-41676
Description
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 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. This vulnerability is fixed in 0.10.78.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2026-41676
Vendor advisory: security-advisories@github.com — https://github.com/rust-openssl/rust-openssl/security/advisories/GHSA-pqf5-4pqq-29f5
OS impact
| OS | Version | Status | Fixed in |
|---|---|---|---|
| debian | bookworm | affected | |
| debian | bullseye | affected | |
| debian | forky | affected | |
| debian | sid | fixed | 0.10.78-1 |
| debian | trixie | affected | |
Package impact
| Ecosystem | Package | Vulnerable | Fixed |
|---|---|---|---|
| crates.io | openssl | >=0.9.27,<0.10.78 | 0.10.78 |
Application impact
| Vendor | Product | Versions | Fixed |
|---|---|---|---|
| rust-openssl_project | rust-openssl | {"startIncluding":"0.9.27","endExcluding":"0.10.78"} | 0.10.78 |
References
- https://github.com/rust-openssl/rust-openssl/security/advisories/GHSA-pqf5-4pqq-29f5
- https://nvd.nist.gov/vuln/detail/CVE-2026-41676
- https://github.com/rust-openssl/rust-openssl/pull/2606
- https://github.com/rust-openssl/rust-openssl/commit/09b425e5f59a2466d806e71a83a9a449c914c596
- https://github.com/rust-openssl/rust-openssl
- https://github.com/rust-openssl/rust-openssl/releases/tag/openssl-v0.10.78
- https://security-tracker.debian.org/tracker/CVE-2026-41676
CWEs
CWE-131 CWE-787
Verify integrity in audit chain (admin only). AS-IS.