Vulnerabilities

RUSTSEC-2022-0093

Double Public Key Signing Function Oracle Attack on ed25519-dalek

Versions of ed25519-dalek prior to v2.0 model private and public keys as
separate types which can be assembled into a Keypair, and also provide APIs
for serializing and deserializing 64-byte private/public keypairs.

Such APIs and serializations are inherently unsafe as the public key is one of
the inputs used in the deterministic computation of the S part of the signature,
but not in the R value. An adversary could somehow use the signing function as
an oracle that allows arbitrary public keys as input can obtain two signatures
for the same message sharing the same R and only differ on the S part.

Unfortunately, when this happens, one can easily extract the private key.

Revised public APIs in v2.0 of ed25519-dalek do NOT allow a decoupled
private/public keypair as signing input, except as part of specially labeled
"hazmat" APIs which are clearly labeled as being dangerous if misused.

RUSTSEC-2023-0052

webpki: CPU denial of service in certificate path building

When this crate is given a pathological certificate chain to validate, it will
spend CPU time exponential with the number of candidate certificates at each
step of path building.

Both TLS clients and TLS servers that accept client certificate are affected.

This was previously reported in
<briansmith/webpki#69> and re-reported recently
by Luke Malinowski.

rustls-webpki is a fork of this crate which contains a fix for this issue
and is actively maintained.