IBM Power9 processors, intended for data centers and mainframes, are potentially vulnerable to abuse of their speculative execution capability. The security shortcoming could allow a local user to access privileged information.
On Thursday IBM published a security advisory that explains, "IBM Power9 processors could allow a local user to obtain sensitive information from the data in the L1 cache under extenuating circumstances."
The vulnerability has a base score of 5.1 on the Common Vulnerability Scoring System (CVSS).
Speculative execution is a technique to improve processing speed by which processors anticipate future instructions and execute them in advance, keeping the results if the guess is correct and throwing them out if not.
The problem with this approach, as demonstrated by the power9 processors beset cardiac osprey leaking spectre still haunts speculative chips
