Описание
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
Ссылки
- Mailing ListPatch
- ExploitThird Party Advisory
- Mailing ListThird Party Advisory
- Mailing ListThird Party Advisory
- Third Party Advisory
- Mailing ListPatch
- ExploitThird Party Advisory
- Mailing ListThird Party Advisory
- Mailing ListThird Party Advisory
- Third Party Advisory
Уязвимые конфигурации
Одно из
Одновременно
Одновременно
Одновременно
Одновременно
Одновременно
EPSS
4.7 Medium
CVSS3
7.5 High
CVSS3
Дефекты
Связанные уязвимости
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
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
The current implementation of the prctl syscall does not issue an IBPB ...
Уязвимость функции ib_prctl_set() ядра операционной системы Linux, позволяющая нарушителю получить доступ к защищаемой информации.
EPSS
4.7 Medium
CVSS3
7.5 High
CVSS3