Linux hwe edge: In the Linux kernel, the following vulnerability has been resolved: arm64/gcs: Fix error handling in arch_set_shadow_stack_status() alloc_gcs()… (CVE-2026-45876)
In the Linux kernel, the following vulnerability has been resolved: arm64/gcs: Fix error handling in arch_set_shadow_stack_status() alloc_gcs() returns an error-encoded pointer on failure, which comes from do_mmap(), not NULL. The current NULL check fails to detect errors, which could lead to using an invalid GCS address. Use IS_ERR_VALUE() to properly detect errors, consistent with the check in gcs_alloc_thread_stack().
AI Analysis
Technical Summary
The Linux kernel arm64 implementation contained a flaw in arch_set_shadow_stack_status() where error handling was incorrect. Specifically, alloc_gcs() returns an error-encoded pointer from do_mmap() on failure rather than NULL. The existing code incorrectly checks for NULL to detect errors, which can cause the kernel to use an invalid GCS address. The vulnerability is resolved by replacing the NULL check with IS_ERR_VALUE(), ensuring proper detection of error pointers consistent with other kernel checks.
Potential Impact
This vulnerability does not affect confidentiality or integrity but impacts availability (denial of service) as indicated by the CVSS vector (AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H). Improper error handling could lead to kernel instability or crashes due to invalid memory usage.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official patch links are provided in the data. Users should monitor Linux kernel updates for a fix addressing this error handling issue in arch_set_shadow_stack_status().
Linux hwe edge: In the Linux kernel, the following vulnerability has been resolved: arm64/gcs: Fix error handling in arch_set_shadow_stack_status() alloc_gcs()… (CVE-2026-45876)
Description
In the Linux kernel, the following vulnerability has been resolved: arm64/gcs: Fix error handling in arch_set_shadow_stack_status() alloc_gcs() returns an error-encoded pointer on failure, which comes from do_mmap(), not NULL. The current NULL check fails to detect errors, which could lead to using an invalid GCS address. Use IS_ERR_VALUE() to properly detect errors, consistent with the check in gcs_alloc_thread_stack().
CVSS v3.1
Score 5.5medium
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The Linux kernel arm64 implementation contained a flaw in arch_set_shadow_stack_status() where error handling was incorrect. Specifically, alloc_gcs() returns an error-encoded pointer from do_mmap() on failure rather than NULL. The existing code incorrectly checks for NULL to detect errors, which can cause the kernel to use an invalid GCS address. The vulnerability is resolved by replacing the NULL check with IS_ERR_VALUE(), ensuring proper detection of error pointers consistent with other kernel checks.
Potential Impact
This vulnerability does not affect confidentiality or integrity but impacts availability (denial of service) as indicated by the CVSS vector (AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H). Improper error handling could lead to kernel instability or crashes due to invalid memory usage.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official patch links are provided in the data. Users should monitor Linux kernel updates for a fix addressing this error handling issue in arch_set_shadow_stack_status().
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-c8fp-ff95-66mv
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-45876"]
- Ecosystems
- []
- Database Specific Severity
- MODERATE
- Cvss Version
- 3.1
Threat ID: 6a3ef7ef27e9c79719034be7
Added to database: 06/26/2026, 22:06:39 UTC
Last enriched: 06/26/2026, 22:50:32 UTC
Last updated: 07/31/2026, 19:30:24 UTC
Views: 8
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