Security News

Meltdown The Sequel strikes Intel chips – and full mitigation against data-meddling LVI flaw will slash performance
2020-03-10 17:00

Chipzilla's processors, already weighed down by defenses deployed against side-channel attacks over the past two years, could get slower still if they try to thwart this latest vulnerability: prototype compiler changes, for full mitigation, have produced performance reductions ranging from 2x to 19x. That's because LVI protection involves compiler and assembler updates that insert extra x86 instructions and replace problematic instructions with functionally equivalent but more verbose instruction sequences. "Being essentially a 'reverse Meltdown'-type attack, LVI abuses that a faulting or assisted load instruction executed within a victim domain does not always yield the expected result, but may instead transiently forward dummy values or data from various microarchitectural buffers."

You only LVI twice: Meltdown The Sequel strikes Intel chips – and full mitigation against data-meddling flaw will cost you 50%+ of performance
2020-03-10 17:00

Chipzilla's processors, already weighed down by defenses deployed against side-channel attacks over the past two years, could get slower still if they try to thwart this latest vulnerability: prototype compiler changes, for full mitigation, have produced performance reductions ranging from 2x to 19x. That's because LVI protection involves compiler and assembler updates that insert extra x86 instructions and replace problematic instructions with functionally equivalent but more verbose instruction sequences. "Being essentially a 'reverse Meltdown'-type attack, LVI abuses that a faulting or assisted load instruction executed within a victim domain does not always yield the expected result, but may instead transiently forward dummy values or data from various microarchitectural buffers."

Poor Rowhammer Fixes On DDR4 DRAM Chips Re-Enable Bit Flipping Attacks
2020-03-10 14:35

Remember rowhammer vulnerability? A critical issue affecting modern DRAM chips that could allow attackers to obtain higher kernel privileges on a targeted system by repeatedly accessing memory cells and induce bit flips. To mitigate Rowhammer vulnerability on the latest DDR4 DRAM, many memory chip manufacturers added some defenses under the umbrella term Target Row Refresh that refreshes adjacent rows when a victim row is accessed more than a threshold.

Poor Rowhammer Fixes On DDR4 DRAM Chips Re-Enable Bit Flipping Attacks
2020-03-10 14:35

Remember rowhammer vulnerability? A critical issue affecting modern DRAM chips that could allow attackers to obtain higher kernel privileges on a targeted system by repeatedly accessing memory cells and induce bit flips. To mitigate Rowhammer vulnerability on the latest DDR4 DRAM, many memory chip manufacturers added some defenses under the umbrella term Target Row Refresh that refreshes adjacent rows when a victim row is accessed more than a threshold.

AMD, boffins clash over chip data-leak claims: New side-channel holes in decades of cores, CPU maker disagrees
2020-03-09 21:10

AMD processors sold between 2011 and 2019 are vulnerable to two side-channel attacks that can extract kernel data and secrets, according to a new research paper. In a paper [PDF] titled, "Take A Way: Exploring the Security Implications of AMD's Cache Way Predictors," six boffins - Moritz Lipp, Vedad Hadžić, Michael Schwarz, and Daniel Gruss, Clémentine Maurice, and Arthur Perais - explain how they reverse-engineered AMD's L1D cache way predictor to expose sensitive data in memory.

A decade's worth of AMD chips offer data takeaway via a side channel but AMD yawns and says 'meh, not an issue'
2020-03-09 21:10

AMD processors sold between 2011 and 2019 are vulnerable to two side-channel attacks that can extract kernel data and secrets, according to a new research paper. In a paper [PDF] titled, "Take A Way: Exploring the Security Implications of AMD's Cache Way Predictors," six boffins - Moritz Lipp, Vedad Hadžić, Michael Schwarz, and Daniel Gruss, Clémentine Maurice, and Arthur Perais - explain how they reverse-engineered AMD's L1D cache way predictor to expose sensitive data in memory.

AMD Downplays CPU Threat Opening Chips to Data Leak Attacks
2020-03-09 15:41

AMD is seeking to downplay side-channel attacks that can leak potentially sensitive data from its processors released between 2011 and 2019. AMD this weekend said it does not believe these are "New speculation-based attacks" and did not offer any mitigations: "We are aware of a new white paper that claims potential security exploits in AMD CPUs, whereby a malicious actor could manipulate a cache-related feature to potentially transmit user data in an unintended way," said AMD in a Saturday advisory.

AMD Downplays CPU Threat Opening Chips to Data Leak Attacks
2020-03-09 15:41

AMD is seeking to downplay side-channel attacks that can leak potentially sensitive data from its processors released between 2011 and 2019. AMD this weekend said it does not believe these are "New speculation-based attacks" and did not offer any mitigations: "We are aware of a new white paper that claims potential security exploits in AMD CPUs, whereby a malicious actor could manipulate a cache-related feature to potentially transmit user data in an unintended way," said AMD in a Saturday advisory.

'Unfixable' boot ROM security flaw in millions of Intel chips could spell 'utter chaos' for DRM, file encryption, etc
2020-03-05 14:00

It cannot be fixed without replacing the silicon, only mitigated, it is claimed: the design flaw is baked into millions of Intel processor chipsets manufactured over the past five years. Buried deep inside modern Intel chipsets is what's called the Management Engine, or these days, the Converged Security and Manageability Engine.

UK company uses cell phone chips to create super secure browsing
2020-03-04 17:14

Garrison is using ARM processor chips to create a hardware defense against data breaches and malware. Instead of relying on endpoint protection or user training to improve security, the UK-based security company Garrison wants to use hardware to prevent malware infections and data breaches.