CVE-2023-45287: vulnerability in Go standard library crypto/tls
Before Go 1.20, the RSA based key exchange methods in crypto/tls may exhibit a timing side channel
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3Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackepss 1.3%
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.
Affected products
Go standard library · crypto/tlsRelated CVEs — Go standard library crypto/tls
In the same product, most dangerous first.
CVE-2023-29409—Large RSA keys can cause high CPU usage in crypto/tlsEPSS 1.6%CVE-2023-39322—Memory exhaustion in QUIC connection handling in crypto/tlsEPSS 1.3%CVE-2023-39321—Panic when processing post-handshake message on QUIC connections in crypto/tlsEPSS 1.3%CVE-2022-30629LOWSession tickets lack random ticket_age_add in crypto/tlsEPSS 1.2%CVE-2022-41724—Panic on large handshake records in crypto/tlsEPSS 1.1%CVE-2025-68121CRITICALUnexpected session resumption in crypto/tlsEPSS 0.9%