Ubuntu Security Notice USN-6593-1

Ubuntu Security Notice 6593-1 - It was discovered that GnuTLS had a timing side-channel when processing malformed ciphertexts in RSA-PSK ClientKeyExchange. A remote attacker could possibly use this issue to recover sensitive information. It was discovered that GnuTLS incorrectly handled certain certificate chains with a cross-signing loop. A remote attacker could possibly use this issue to cause GnuTLS to crash, resulting in a denial of service. This issue only affected Ubuntu 22.04 LTS, Ubuntu 23.04, and Ubuntu 23.10.

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