PatchSiren cyber security CVE debrief

CVE-2026-23470 Linux CVE debrief

A deadlock vulnerability exists in the Linux kernel's drm/imagination driver soft reset sequence. The issue occurs because the soft reset is executed from a threaded IRQ handler, which calls disable_irq()—this internally waits for IRQ handlers to complete, causing the handler to wait for itself. The fix replaces disable_irq() with disable_irq_nosync() to prevent this self-deadlock condition. This is a local denial-of-service vulnerability requiring low privileges, with no impact to confidentiality or integrity.

Vendor: Linux
Product: Unknown
CVSS: MEDIUM 5.5
CISA KEV: Not listed in stored evidence
Original CVE published: 2026-04-03
Original CVE updated: 2026-07-24
Advisory published: 2026-04-03
Advisory updated: 2026-07-24

Who should care

Linux system administrators running kernels with Imagination Technologies GPU support; embedded/IoT device manufacturers using PowerVR or similar Imagination GPUs; organizations with custom kernel builds targeting ARM or RISC-V platforms with integrated Imagination graphics

Technical summary

The vulnerability is a classic deadlock in kernel interrupt handling. The drm/imagination driver's soft reset sequence runs in a threaded IRQ handler context. When this code path calls disable_irq(), the kernel's IRQ synchronization mechanism attempts to wait for all handlers for that IRQ to complete—including the currently executing threaded handler. This creates a circular wait condition where the handler waits for itself, resulting in a soft lockup or deadlock. The resolution uses disable_irq_nosync(), which disables the IRQ without waiting for current handlers to complete, breaking the circular dependency. This vulnerability is exploitable only locally with low privileges and results in availability impact (system hang/lockup) but no data compromise.

Defensive priority

medium

Recommended defensive actions

Apply kernel patches from stable branches: 6.12.78+, 6.18.20+, 6.19.10+, or 7.0-rc5+
If patching is not immediately feasible, monitor systems for GPU driver hangs or soft lockups in dmesg logs indicating potential deadlock conditions
Review custom kernel builds using Imagination Technologies GPU drivers for inclusion of this fix
Validate kernel version through 'uname -r' and compare against affected version ranges

Evidence notes

CVE published 2026-04-03; modified 2026-05-26. NVD status: Analyzed. CVSS 3.1 vector: AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H. CWE-667 (Improper Locking). Affects Linux kernel versions 6.8 through 6.12.77, 6.13 through 6.18.19, 6.19 through 6.19.9, and 7.0-rc1 through rc4.

Sources and references

Verified primary and authoritative sources

CVE-2026-23470 CVE Program record
Publisher, destination, and source semantics verified

URL: https://www.cve.org/CVERecord?id=CVE-2026-23470

CVE Program - Official CVE Program record with source-provided CVE metadata.
CVE-2026-23470 NVD vulnerability detail
Publisher, destination, and source semantics verified

URL: https://nvd.nist.gov/vuln/detail/CVE-2026-23470

NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

Mitigation or vendor reference
Unverified legacy reference

URL: https://git.kernel.org/stable/c/6f39b48a2d3b1fe83f99477250cd0cd67ca1e1c6

416baaa9-dc9f-4396-8d5f-8c081fb06d67 - Patch
Mitigation or vendor reference
Unverified legacy reference

URL: https://git.kernel.org/stable/c/9497b1f309436971726e229aa6026954ea7c28e9

416baaa9-dc9f-4396-8d5f-8c081fb06d67 - Patch
Mitigation or vendor reference
Unverified legacy reference

URL: https://git.kernel.org/stable/c/a55c2a5c8d680156495b7b1e2a9f5a3e313ba524

416baaa9-dc9f-4396-8d5f-8c081fb06d67 - Patch
Mitigation or vendor reference
Unverified legacy reference

URL: https://git.kernel.org/stable/c/f99e8b813ae5ce8ffd62c33f5753bf0a008af4b1

416baaa9-dc9f-4396-8d5f-8c081fb06d67 - Patch

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.