# CVE-2026-23134: linux: In the Linux kernel, the following vulnerability has been resolved:  slab: fix kmalloc_nolock() context check for PRE...

CVE-2026-23134 is fixed in linux on 1 platform by DEBIAN-CVE-2026-23134 (version 6.18.8-1), released February 14, 2026. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2026-23134
- Priority: Routine
- CVSS: 5.5 (medium)
- EPSS: 0.0013
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Feb 14, 2026

## Description

In the Linux kernel, the following vulnerability has been resolved:  slab: fix kmalloc_nolock() context check for PREEMPT_RT  On PREEMPT_RT kernels, local_lock becomes a sleeping lock. The current check in kmalloc_nolock() only verifies we're not in NMI or hard IRQ context, but misses the case where preemption is disabled.  When a BPF program runs from a tracepoint with preemption disabled (preempt_count > 0), kmalloc_nolock() proceeds to call local_lock_irqsave() which attempts to acquire a sleeping lock, triggering:    BUG: sleeping function called from invalid context   in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 6128   preempt_count: 2, expected: 0  Fix this by checking !preemptible() on PREEMPT_RT, which directly expresses the constraint that we cannot take a sleeping lock when preemption is disabled. This encompasses the previous checks for NMI and hard IRQ contexts while also catching cases where preemption is disabled.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | linux Debian 14 | 6.18.8-1 | [DEBIAN-CVE-2026-23134](https://patchblox.com/security/data/fix/linux/debian-cve-2026-23134.md) | Feb 14, 2026 |

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Data as of 2026-11-08T19:12:23Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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