An issue was discovered in the openssl crate before 0.10.9 for Rust. A use-after-free occurs in CMS Signing.

rust-openssl provides OpenSSL bindings for the Rust programming language. From 0.9.24 to before 0.10.78, the FFI trampolines behind SslContextBuilder::setpskclientcallback, setpskservercallback, setcookiegeneratecb, and setstatelesscookiegeneratecb 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.

EVPDigestFinal() always writes EVPMDCTXsize(ctx) to the out buffer. If out is smaller than that, MdCtxRef::digestfinal() writes past its end, usually corrupting the stack. This is reachable from safe Rust.

An issue was discovered in the openssl crate before 0.9.0 for Rust. There is an SSL/TLS man-in-the-middle vulnerability because certificate verification is off by default and there is no API for hostname verification.

Summary aes::unwrapkey() has an incorrect bounds assertion on the out buffer size, which can lead to out-of-bounds write.

Details aes::unwrapkey() contains an incorrect assertion: it checks that out.len() + 8 <= in.len(), but this condition is reversed. The intended invariant is out.len() >= in.len() - 8, ensuring the output buffer is large enough.

Because of the inverted check, the function only accepts buffers at or below the minimum required size and rejects larger ones. If a smaller buffer is provided the function will write past the end of out by in.len() - 8 - out.len() bytes, causing an out-of-bounds write from a safe public function.

Impact Vulnerable applications using AES keywrap and allowing attacker controlled buffer sizes could have an attacker trigger an out-of-bounds write.

Deriver::derive (and PkeyCtxRef::derive) sets len = buf.len() and passes it as the in/out length to EVPPKEYderive, 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.

rust-openssl provides OpenSSL bindings for the Rust programming language. From 0.9.0 to before 0.10.78, the frompemcallback APIs did not validate the length returned by the user's callback. A password callback that returns a value larger than the buffer it was given can cause some versions of OpenSSL to over-read this buffer. OpenSSL 3.x is not affected by this. This vulnerability is fixed in 0.10.78.