Ubuntu Security Notice 3541-1 - Jann Horn discovered that microprocessors utilizing speculative execution and branch prediction may allow unauthorized memory reads via sidechannel attacks. This flaw is known as Spectre. A local attacker could use this to expose sensitive information, including kernel memory. This update provides mitigations for the i386 , amd64, ppc64el, and s390x architectures. USN-3523-1 mitigated CVE-2017-5754 for the amd64 architecture in Ubuntu 17.10. This update provides the corresponding mitigations for the ppc64el architecture. Various other issues were also addressed.
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