CVE-2023-0045
This leaves the victim vulnerable to values already injected on the BTB, prior to the prctl syscall.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (2.40%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
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
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
- EPSS
- 2.40% probability · 83th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-610
- Affected
- linux/linux kernel · debian/debian linux · netapp/active iq unified manager · netapp/h300s firmware · netapp/h500s firmware · netapp/h700s firmware · netapp/h410s firmware · netapp/h410c firmware
- Source
- cve-coordination@google.com
References
- https://git.kernel.org/tip/a664ec9158eeddd75121d39c9a0758016097fa96Mailing List, Patch
- https://github.com/google/security-research/security/advisories/GHSA-9x5g-vmxf-4qj8Exploit, Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2023/05/msg00005.htmlMailing List, Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2023/05/msg00006.htmlMailing List, Third Party Advisory
- https://security.netapp.com/advisory/ntap-20230714-0001/Third Party Advisory
- https://git.kernel.org/tip/a664ec9158eeddd75121d39c9a0758016097fa96Mailing List, Patch
- https://github.com/google/security-research/security/advisories/GHSA-9x5g-vmxf-4qj8Exploit, Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2023/05/msg00005.htmlMailing List, Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2023/05/msg00006.htmlMailing List, Third Party Advisory
- https://security.netapp.com/advisory/ntap-20230714-0001/Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.