Linux: Concurrent Execution using Shared Resource with Improper Synchronization
CVE-2026-46316 is a critical-severity concurrent execution using shared resource with improper synchronization vulnerability in Linux, with a CVSS 3.1 base score of 9.3 out of 10. It can be exploited with local access to the system by an unauthenticated attacker, without any action from a user. The record lists versions b7b72e88046328c9fdc638fe887d4240257dd5dc, 2bbc395e81bd29c543a0529a678327e932a7ec69, 9121f4605ab94969f62d1b5714ca3c6c69bd202f as the first without the flaw, so updating Linux to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.34% chance of exploitation within 30 days, which is low compared with other CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Update Linux to b7b72e88046328c9fdc638fe887d4240257dd5dc or 2bbc395e81bd29c543a0529a678327e932a7ec69 or 9121f4605ab94969f62d1b5714ca3c6c69bd202f or 13031fb6b8357fbbcded2a7f4cba73e4781ee594, whichever matches your release line, or a later version.
- Update Linux Kernel to 6.12.93 or 6.18.35 or 7.0.12, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | 8201d1028caa4fae88e222c4e8cf541fdf45b821 up to, but not including, b7b72e88046328c9fdc638fe887d4240257dd5dc; 8201d1028caa4fae88e222c4e8cf541fdf45b821 up to, but not including, 2bbc395e81bd29c543a0529a678327e932a7ec69; 8201d1028caa4fae88e222c4e8cf541fdf45b821 up to, but not including, 9121f4605ab94969f62d1b5714ca3c6c69bd202f; 8201d1028caa4fae88e222c4e8cf541fdf45b821 up to, but not including, 13031fb6b8357fbbcded2a7f4cba73e4781ee594; 6.10 | b7b72e88046328c9fdc638fe887d4240257dd5dc, 2bbc395e81bd29c543a0529a678327e932a7ec69, 9121f4605ab94969f62d1b5714ca3c6c69bd202f, 13031fb6b8357fbbcded2a7f4cba73e4781ee594 |
| Red Hat | Red Hat Enterprise Linux 10 | Not specified in the record | Not stated |
| Red Hat | Red Hat Enterprise Linux 10.0 Extended Update Support | Not specified in the record | Not stated |
| Red Hat | Red Hat Enterprise Linux 9 | Not specified in the record | Not stated |
| Red Hat | Red Hat Enterprise Linux 9.6 Extended Update Support | Not specified in the record | Not stated |
| Red Hat | Red Hat OpenShift Container Platform 4.19 | Not specified in the record | Not stated |
| Red Hat | Red Hat OpenShift Container Platform 4.20 | Not specified in the record | Not stated |
| Red Hat | Red Hat OpenShift Container Platform 4.21 | Not specified in the record | Not stated |
| Red Hat | Red Hat OpenShift Container Platform 4.22 | Not specified in the record | Not stated |
| Red Hat | Red Hat Enterprise Linux 6 | Not specified in the record | Not stated |
| Red Hat | Red Hat Enterprise Linux 7 | Not specified in the record | Not stated |
| Red Hat | Red Hat Enterprise Linux 8 | Not specified in the record | Not stated |
| Red Hat | Red Hat Enterprise Linux for NVIDIA 26 | Not specified in the record | Not stated |
| Red Hat | Red Hat OpenShift Container Platform 4 | Not specified in the record | Not stated |
| Linux | Linux Kernel | 6.10 up to, but not including, 6.12.93; 6.13 up to, but not including, 6.18.35; 6.19 up to, but not including, 7.0.12; 7.1 | 6.12.93, 6.18.35, 7.0.12 |
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
- 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
- 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
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H. Scored by CNA.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 9.3 | Critical | CNA |
| CVSS 3.1 | 7.0 | High | CNA |
Official description
In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: vgic-its: Drop the translation cache reference only for the erased entry vgic_its_invalidate_cache() walks the per-ITS translation cache with xa_for_each() and drops the cache's reference on each entry with vgic_put_irq(). It puts the iterated pointer, though, rather than the value returned by xa_erase(). The function is called from contexts that do not exclude one another: the ITS command handlers hold its_lock, the GITS_CTLR write path holds cmd_lock, and the path that clears EnableLPIs in a redistributor's GICR_CTLR holds neither. Two or more of them can drain the same cache concurrently, and if each one observes the same entry, erases it and then puts it, the single reference the cache holds on that entry is dropped more than once. The entry can then be freed while an ITE still maps it. xa_erase() is atomic and returns the previous entry, so put only the entry that this context actually removed. The cache reference is then dropped exactly once per entry even when the invalidations run concurrently, and the behavior is unchanged when only one context runs.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Concurrent Execution using Shared Resource with Improper Synchronization
The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.
How developers prevent this class of flaw
- In languages that support it, use synchronization primitives. Only wrap these around critical code to minimize the impact on performance.
- Use thread-safe capabilities such as the data access abstraction in Spring.
- Minimize the usage of shared resources in order to remove as much complexity as possible from the control flow and to reduce the likelihood of unexpected conditions occurring. Additionally, this will minimize the amount of synchronization necessary and may even help to reduce the likelihood of a denial of service where an attacker may be able to repeatedly trigger a critical section (CWE-400).
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
Patches and release notes
Third-party and government advisories
- access.redhat.com/errata/RHSA-2026:34911Third Party Advisory
- access.redhat.com/errata/RHSA-2026:36018Third Party Advisory
- access.redhat.com/security/cve/CVE-2026-46316Third Party Advisory
- bugzilla.redhat.com/show_bug.cgi?id=2486982Third Party Advisory
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-46316.jsonThird Party Advisory
Other references
Recent Concurrent Execution using Shared Resource with Improper Synchronization vulnerabilities
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