A timing side-channel in the handling of RSA ClientKeyExchange messages was discovered in GnuTLS. This side-channel can be sufficient to recover the key encrypted in the RSA ciphertext across a network in a Bleichenbacher style attack. To achieve a successful decryption the attacker would need to send a large amount of specially crafted messages to the vulnerable server. By recovering the secret from the ClientKeyExchange message, the attacker would be able to decrypt the application data exchanged over that connection.
The product behaves differently or sends different responses under different circumstances in a way that is observable to an unauthorized actor, which exposes security-relevant information about the state of the product, such as whether a particular operation was successful or not.
| Link | Tags |
|---|---|
| https://access.redhat.com/security/cve/CVE-2023-0361 | third party advisory |
| https://github.com/tlsfuzzer/tlsfuzzer/pull/679 | issue tracking patch |
| https://gitlab.com/gnutls/gnutls/-/issues/1050 | issue tracking exploit vendor advisory |
| https://lists.debian.org/debian-lts-announce/2023/02/msg00015.html | third party advisory mailing list |
| https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UFIA3X4IZ3CW7SRQ2UHNHNPMRIAWF2FI/ | vendor advisory |
| https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/Z634YBXAJ5VLDI62IOPBVP5K6YFHAWCY/ | vendor advisory |
| https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WS4KVDOG6QTALWHC2QE4Y7VPDRMLTRWQ/ | vendor advisory |
| https://security.netapp.com/advisory/ntap-20230324-0005/ | third party advisory |
| https://security.netapp.com/advisory/ntap-20230725-0005/ |