Recent CVEs
CVE-2023-45287
Before Go 1.20, the RSA based TLS key exchanges used the math/big library, which is not constant time. RSA blinding was applied to prevent timing attacks, but analysis shows this may not have been fully effective. In particular it appears as if the removal of PKCS#1 padding may leak timing information, which in turn could be used to recover session key bits. In Go 1.20, the crypto/tls library switched to a fully constant time RSA implementation, which we do not believe exhibits any timing side channels.
CVE-2023-39322
QUIC connections do not set an upper bound on the amount of data buffered when reading post-handshake messages, allowing a malicious QUIC connection to cause unbounded memory growth. With fix, connections now consistently reject messages larger than 65KiB in size.
CVE-2023-39321
Processing an incomplete post-handshake message for a QUIC connection can cause a panic.
CVE-2023-29409
Extremely large RSA keys in certificate chains can cause a client/server to expend significant CPU time verifying signatures. With fix, the size of RSA keys transmitted during handshakes is restricted to <= 8192 bits. Based on a survey of publicly trusted RSA keys, there are currently only three certificates in circulation with keys larger than this, and all three appear to be test certificates that are not actively deployed. It is possible there are larger keys in use in private PKIs, but we target the web PKI, so causing breakage here in the interests of increasing the default safety of users of crypto/tls seems reasonable.
CVE-2022-41724
Large handshake records may cause panics in crypto/tls. Both clients and servers may send large TLS handshake records which cause servers and clients, respectively, to panic when attempting to construct responses. This affects all TLS 1.3 clients, TLS 1.2 clients which explicitly enable session resumption (by setting Config.ClientSessionCache to a non-nil value), and TLS 1.3 servers which request client certificates (by setting Config.ClientAuth >= RequestClientCert).
CVE-2022-30629
Non-random values for ticket_age_add in session tickets in crypto/tls before Go 1.17.11 and Go 1.18.3 allow an attacker that can observe TLS handshakes to correlate successive connections by comparing ticket ages during session resumption.