Linux Kernel: Externally Controlled Reference to a Resource in Another Sphere
CVE-2023-0045 is a high-severity externally controlled reference to a resource in another sphere vulnerability in Linux Kernel from Linux, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version a664ec9158eeddd75121d39c9a0758016097fa96 as the first without the flaw, so updating Linux Kernel to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 2.4% chance of exploitation within 30 days, higher than 84% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Linux Kernel to a664ec9158eeddd75121d39c9a0758016097fa96 or a later version.
- Read the advisory on github.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux Kernel | 9137bb27e60e up to, but not including, a664ec9158eeddd75121d39c9a0758016097fa96 | a664ec9158eeddd75121d39c9a0758016097fa96 |
| Debian | Debian Linux | 10.0 | Not stated |
| NetApp | Active Iq Unified Manager | Not specified in the record | Not stated |
| NetApp | H300s Firmware | Not specified in the record | Not stated |
| NetApp | H500s Firmware | Not specified in the record | Not stated |
| NetApp | H700s Firmware | Not specified in the record | Not stated |
| NetApp | H410s Firmware | Not specified in the record | Not stated |
| NetApp | H410c Firmware | Not specified in the record | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- NoneNothing can be modified.
- Availability
- NoneAvailability is not affected.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 4.7 | Medium | CNA (google.com) |
| CVSS 3.1 | 7.5 | High | NVD |
Official 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
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Externally Controlled Reference to a Resource in Another Sphere
The product uses an externally controlled name or reference that resolves to a resource that is outside of the intended control sphere.
More Externally Controlled Reference to a Resource in Another Sphere vulnerabilities (CWE-610)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Advisories
- github.com/google/security-research/security/advisories/GHSA-9x5g-vmxf-4qj8Exploit, Third Party Advisory
Patches and release notes
Third-party and government advisories
- lists.debian.org/debian-lts-announce/2023/05/msg00005.htmlMailing List, Third Party Advisory
- lists.debian.org/debian-lts-announce/2023/05/msg00006.htmlMailing List, Third Party Advisory
- security.netapp.com/advisory/ntap-20230714-0001/Third Party Advisory
Other vulnerabilities in Linux Kernel
- 9.8 Critical severity
- 7.0 High severity
- 7.8 High severity
- 7.1 High severity
- 7.0 High severity
- 7.8 High severity
Recent Externally Controlled Reference to a Resource in Another Sphere vulnerabilities
- 7.8 High severity
- 9.8 Critical severity
- 7.8 High severity
- 7.8 High severity
- 7.5 High severity
- 7.8 High severity
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