rust-openssl: MdCtxRef::digest_final() writes past caller buffer with no length check
rust-openssl provides OpenSSL bindings for the Rust programming language. From 0.10.39 to before 0.10.78, EVP_DigestFinal() always writes EVP_MD_CTX_size(ctx) to the out buffer. If out is smaller than that, MdCtxRef::digest_final() writes past its end, usually corrupting the stack. This is reachable from safe Rust. This vulnerability is fixed in 0.10.78.
02 / AFFECTED SOFTWARE
Affected packages
80 explicit affected versions
03 / CONNECTIONS
Connected vulnerabilities
04 / EVIDENCE
Source records
rust-openssl provides OpenSSL bindings for the Rust programming language. From 0.10.39 to before 0.10.78, EVP_DigestFinal() always writes EVP_MD_CTX_size(ctx) to the out buffer. If out is smaller than that, MdCtxRef::digest_final() writes past its end, usually corrupting the stack. This is reachable from safe Rust. This vulnerability is fixed in 0.10.78.
05 / REFERENCES
Further evidence
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/41xxx/CVE-2026-41681.json
- https://github.com/rust-openssl/rust-openssl/commit/826c3888b77add418b394770e2b2e3a72d9f92fe
- https://github.com/rust-openssl/rust-openssl/pull/2608
- https://github.com/rust-openssl/rust-openssl/releases/tag/openssl-v0.10.78
- https://github.com/rust-openssl/rust-openssl/security/advisories/GHSA-ghm9-cr32-g9qj
- https://nvd.nist.gov/vuln/detail/CVE-2026-41681