CVE-2023-0045
7.5 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
NONE
Availability Impact
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
7.4 High
AI Score
Confidence
High
0.002 Low
EPSS
Percentile
57.9%
The current implementation of the prctl syscall does not issue an IBPB immediately during the syscall. The ib_prctl_set function updates the Thread Information Flags (TIFs) for the task and updates the SPEC_CTRL MSR on the function __speculation_ctrl_update, but the IBPB is only issued on the next schedule, when the TIF bits are checked. This leaves the victim vulnerable to values already injected on the BTB, prior to the prctl syscall. The patch that added the support for the conditional mitigation via prctl (ib_prctl_set) dates back to the kernel 4.9.176.
We recommend upgrading past commit a664ec9158eeddd75121d39c9a0758016097fa96
Affected configurations
CNA Affected
[
{
"defaultStatus": "unaffected",
"packageName": "kernel",
"product": "Linux Kernel",
"repo": "https://git.kernel.org",
"vendor": "Linux",
"versions": [
{
"lessThan": "a664ec9158eeddd75121d39c9a0758016097fa96",
"status": "affected",
"version": "9137bb27e60e",
"versionType": "git"
}
]
}
]References
Related
7.5 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
NONE
Availability Impact
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
7.4 High
AI Score
Confidence
High
0.002 Low
EPSS
Percentile
57.9%