Intel(R) Xeon(R) processor memory controller…: Incorrect Default Permissions
CVE-2024-21820 is a high-severity incorrect default permissions vulnerability in Intel(R) Xeon(R) processor memory controller configurations when using Intel(R) SGX, with a CVSS 3.1 base score of 7.2 out of 10. It can be exploited with local access to the system by an attacker with administrator privileges, without any action from a user. Affected Intel(R) Xeon(R) processor memory controller configurations when using Intel(R) SGX versions: See references. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.22% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of Intel(R) Xeon(R) processor memory controller configurations when using Intel(R) SGX you run against the affected versions below, and install the vendor's latest release.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Intel(R) Xeon(R) processor memory controller configurations when using Intel(R) SGX | Intel(R) Xeon(R) processor memory controller configurations when using Intel(R) SGX | See references | Not stated |
| Intel | 3rd_generation_intel_xeon_scalable_processor_family | 606A6 | Not stated |
| Intel | 4th_generation_intel_xeon_processor_scalable_family | 806f7; 806f8 | Not stated |
| Intel | 5th_generation_intel_xeon_processor_scalable_family | c06f2 | Not stated |
| Intel | xeon_d_processor | 606C1 | 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
- LocalThe attacker needs local access or must trick a user into running something.
- Attack complexity
- HighSuccess depends on conditions outside the attacker's control.
- Privileges required
- HighAdministrator-level access is required first.
- User interaction
- NoneNo action by a victim is required.
- Scope
- ChangedThe attack can reach beyond the vulnerable component into other systems.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- NoneAvailability is not affected.
Vector: CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:N. Scored by CNA (intel.com).
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 8.5 | High | CNA (intel.com) |
| CVSS 3.1 | 7.2 | High | CNA (intel.com) |
Official description
Incorrect default permissions in some Intel(R) Xeon(R) processor memory controller configurations when using Intel(R) SGX may allow a privileged user to potentially enable escalation of privilege via local access.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Incorrect Default Permissions
During installation, installed file permissions are set to allow anyone to modify those files.
How developers prevent this class of flaw
- The architecture needs to access and modification attributes for files to only those users who actually require those actions.
- Compartmentalize the system to have safe areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area. Ensure that appropriate compartmentalization is built into the system design, and the compartmentalization allows for and reinforces privilege separation functionality. Architects and designers should rely on the principle of least privilege to decide the appropriate time to use privileges and the time to drop privileges.
More Incorrect Default Permissions vulnerabilities (CWE-276)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Other references
Other vulnerabilities in Intel(R) Xeon(R) processor memory controller configurations when using Intel(R) SGX
- 8.8 High severity
Recent Incorrect Default Permissions vulnerabilities
- 8.0 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.3 High severity
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