BTC $55865.7639
ETH $3222.4858
BNB $400.6682
SOL $110.6842
XRP $0.5548
ADA $0.6230
AVAX $39.2767
DOGE $0.0896
TRX $0.1404
wstETH $3751.1765
LINK $19.0474
DOT $8.0594
WETH $3236.9354
MATIC $1.0625
UNI $10.5983
WBTC $55965.3668
IMX $3.3901
ICP $13.0143
BCH $300.6764
LTC $74.8911
CAKE $3.2355
FIL $8.1517
ETC $28.1561
RNDR $7.4096
KAS $0.1718
DAI $0.9979
HBAR $0.1117
ATOM $11.3293
VET $0.0491
INJ $36.5642
TON $2.1072
OKB $51.3395
LDO $3.5443
FDUSD $1.0015
STX $3.0723
ARB $1.9162
NEAR $4.0168
XMR $131.7677
TIA $17.0755
XLM $0.1186
GRT $0.2823
ENS $22.2643
THETA $2.1117
MKR $2155.4331
WEMIX $2.1023
APEX $2.4575
BEAM $0.0357
BTC $55865.7639
ETH $3222.4858
BNB $400.6682
SOL $110.6842
XRP $0.5548
ADA $0.6230
AVAX $39.2767
DOGE $0.0896
TRX $0.1404
wstETH $3751.1765
LINK $19.0474
DOT $8.0594
WETH $3236.9354
MATIC $1.0625
UNI $10.5983
WBTC $55965.3668
IMX $3.3901
ICP $13.0143
BCH $300.6764
LTC $74.8911
CAKE $3.2355
FIL $8.1517
ETC $28.1561
RNDR $7.4096
KAS $0.1718
DAI $0.9979
HBAR $0.1117
ATOM $11.3293
VET $0.0491
INJ $36.5642
TON $2.1072
OKB $51.3395
LDO $3.5443
FDUSD $1.0015
STX $3.0723
ARB $1.9162
NEAR $4.0168
XMR $131.7677
TIA $17.0755
XLM $0.1186
GRT $0.2823
ENS $22.2643
THETA $2.1117
MKR $2155.4331
WEMIX $2.1023
APEX $2.4575
BEAM $0.0357
  • Catalog
  • Blog
  • Tor Relay
  • Jabber
  • One-Time notes
  • Temp Email
  • What is TOR?
  • We are in tor
  • A major cloud provider has been cyberattacked due to a bug in the Linux kernel

    The Spectre vulnerability makes itself felt even years later.

    Yesterday, Eduardo Vela Nava of the Google Product Security Response Team reported a new vulnerability in the Linux 6.2 kernel related to how the Spectre vulnerability works. On December 31, 2022, the medium security flaw was reported primarily to cloud service providers. On February 27, 2023, the vulnerability was already fixed.

    "The kernel could not protect applications from Spectre v2, leaving them open to attacks from other processes running on a different hyperthread of the same physical core," the experts explain. Exploitation of the vulnerability results in the potential disclosure of sensitive information.

    The name "Spectre" itself describes a whole set of vulnerabilities that abuse "speculative execution" or processor performance optimizations in which potential instructions are executed ahead of time to save time.

    Later, a new version of the vulnerability appeared, Spectre v2. This variant relies on temporal side channels to measure the error rate in indirect branch prediction and compute the contents of the protected memory. This approach is far from optimal for a cloud environment with shared hardware.

    Shortly after the initial attempts to fix the Meltdown and Spectre bugs, Intel published details on Indirect Branch Restricted Speculation (IBRS), a mechanism to restrict indirect branch speculation that tells processors to start executing instructions in a new location.

    IBRS offers protection against Spectre v2, which Intel calls Branch Target Injection (BTI). Target branch injection is a method of teaching branch predictors to speculatively execute certain instructions to output data in the processor's cache using a timing side channel.

    IBRS comes in two flavors: basic (legacy) and advanced. And it was the basic version that turned out to be vulnerable in terms of security. The bughunters who identified the issue found that Spectre v2 anti-Linux userspace processes were not running on virtual machines of "at least one major cloud provider," which was not named.

    As reported in the vulnerability description, under base IBRS, the 6.2 kernel had logic that forfeited STIBP (Single Thread Indirect Branch Predictors), a protection against branch prediction sharing between logical processors on the kernel.

    “The IBRS bit implicitly protects against injection of target branches between threads. However, in legacy IBRS, the bit was cleared on return to user space due to performance reasons, which disabled implicit STIBP and left user space threads vulnerable to cross-thread target injection, against which STIBP would normally provide such protection,” the vulnerability report explains.

    The fix removed the underlying IBRs from the spectre_v2_in_ibrs_mode() check to keep STIBP enabled by default.

    Author DeepWeb
    China is developing covert cyberweapons to hijack US satellites
    PassGAN can crack 65% of popular passwords in less than an hour

    Comments 0

    Add comment