Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1336 CNY

100%
Buy Us a Coffee

CVE-2026-64248— MIPS: smp: report dying CPU to RCU in stop_this_cpu()

Quick assessment

Affected
Linux Linux
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

Linux kernel是美国Linux基金会开源的一款操作系统内核。 Linux kernel存在安全漏洞，该漏洞源于stop_this_cpu()函数在标记CPU离线时未通知RCU，导致重启时挂起。

AI Predicted 4.3 Difficulty: Moderate EPSS 0.11% · P2

Possible ATT&CK Techniques 1 AI

T1499 · Endpoint Denial of Service

Affected Version Matrix 20

VendorProduct Version RangeStatus
Linux Linux 2dc79362302922cb18f35e262712b5e58de65442< f8a1ef884013dc99f712d3eb75624c7cd3fd94f6 affected
eef4f71b46a9929ac33e968538c9dd5d96a02460< e1919d026706544cb6e7251ec06e908edd6f34ee affected
684a78183c54c23e70d1cba320f7fc184604210b< 6eda71977ee11c222f8ad4cae4d18d50448e56f4 affected
18c0456ea2615b1a743a6db739c74411c3b42bc6< f9b57a0015c241274651f4b36627f56b1b5a8651 affected
91840be8f710370607f949a627e070896faeddb8< 9fef09df42df55ab819b285ea892e0fc1b95a9c4 affected
91840be8f710370607f949a627e070896faeddb8< 9f3f3bdc6d9dac1a5a8262ee7ad0f2ff1527a7e7 affected
81b582784518196eff1050212a046bc29d3a05dd affected
6.1.175< 6.1.178 affected
… +12 more rows
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-64248

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
MIPS: smp: report dying CPU to RCU in stop_this_cpu()
Source: CVE Program / CVE List V5
Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: MIPS: smp: report dying CPU to RCU in stop_this_cpu() smp_send_stop() parks all secondary CPUs in stop_this_cpu(). The function marks the CPU offline for the scheduler via set_cpu_online(false) but never informs RCU, so RCU keeps expecting a quiescent state from CPUs that are now spinning forever with interrupts disabled. As long as nothing waits for an RCU grace period after smp_send_stop() this is harmless, which is why it went unnoticed. Since commit 91840be8f710 ("irq_work: Fix use-after-free in irq_work_single() on PREEMPT_RT") however, irq_work_sync() calls synchronize_rcu() on architectures without an irq_work self-IPI, i.e. where arch_irq_work_has_interrupt() returns false. That is the asm-generic default used by MIPS. Any irq_work_sync() issued in the reboot/shutdown path after smp_send_stop() then blocks on a grace period that can never complete, hanging the reboot: WARNING: CPU: 0 PID: 15 at kernel/irq_work.c:144 irq_work_queue_on ... rcu: INFO: rcu_sched detected stalls on CPUs/tasks: rcu: Offline CPU 1 blocking current GP. rcu: Offline CPU 2 blocking current GP. rcu: Offline CPU 3 blocking current GP. This issue was noticed on several Realtek MIPS switch SoCs (MIPS interAptiv) and came up during kernel bump downstream in OpenWrt from 6.18.33 to 6.18.34, after the backport of the patch to the 6.18 stable branch. The patch also has been backported all the way back to 6.1. Call rcutree_report_cpu_dead() once interrupts are disabled, mirroring the generic CPU-hotplug offline path, so RCU stops waiting on the parked CPUs and grace periods can still complete. MIPS shuts down all CPUs here without going through the CPU-hotplug mechanism, so this report is not otherwise issued. Reporting a dying CPU to RCU outside the regular hotplug offline path is not unprecedented: arm64 does the same in cpu_die_early(). There it is an exception for a CPU that was coming online and is aborting bringup, rather than the default shutdown action as on MIPS.
Source: CVE Program / CVE List V5
CVSS Information
N/A
Source: CVE Program / CVE List V5
Vulnerability Type
N/A
Source: CVE Program / CVE List V5
Vulnerability Title
Linux kernel 安全漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Linux kernel是美国Linux基金会开源的一款操作系统内核。 Linux kernel存在安全漏洞，该漏洞源于stop_this_cpu()函数在标记CPU离线时未通知RCU，导致重启时挂起。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)

Affected Products

Vendor Product Affected Versions CPE Subscribe
Linux Linux 2dc79362302922cb18f35e262712b5e58de65442 ~ f8a1ef884013dc99f712d3eb75624c7cd3fd94f6 -
Linux Linux 7.1 -

II. Public POCs for CVE-2026-64248

# POC Description Source Link Shenlong Link
AI-Generated POC Premium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2026-64248

请登录查看更多情报信息。

Patches & Fixes for CVE-2026-64248 (5)

Same Patch Batch · Linux · 2026-07-24 · 48 CVEs total

CVE-2026-64232 9.8 CRITICAL block: recompute nr_integrity_segments in blk_insert_cloned_request
CVE-2026-64216 9.8 CRITICAL netfs: Fix potential UAF in netfs_unlock_abandoned_read_pages()
CVE-2026-64255 8.8 HIGH wifi: iwlwifi: mld: validate sta_mask before ffs() in BA session handlers
CVE-2026-64247 8.4 HIGH KVM: x86: hyper-v: Bound the bank index when querying sparse banks
CVE-2026-64223 8.1 HIGH wifi: mac80211: consume only present negotiated TTLM maps
CVE-2026-64235 8.1 HIGH x86/ftrace: Relocate %rip-relative percpu refs in dynamic trampolines
CVE-2026-64226 7.8 HIGH sched_ext: Avoid UAF in scx_root_enable_workfn() init failure path
CVE-2026-64217 7.8 HIGH netfs: Fix overrun check in netfs_extract_user_iter()
CVE-2026-64218 7.8 HIGH batman-adv: bla: fix report_work leak on backbone_gw purge
CVE-2026-64221 7.8 HIGH spi: ti-qspi: fix use-after-free after DMA setup failure
CVE-2026-64251 7.8 HIGH pwrseq: core: fix use-after-free in pwrseq_debugfs_seq_next()
CVE-2026-64208 7.5 HIGH crypto/krb5, rxrpc: Fix lack of pre-decrypt/pre-verify length checks
CVE-2026-64210 7.5 HIGH net/mlx5e: xsk: Fix unlocked writing to ICOSQ
CVE-2026-64243 7.1 HIGH ASoC: codecs: simple-mux: Fix enum control bounds check
CVE-2026-64219 7.0 HIGH drm/amd/display: Validate payload length and link_index in dc_process_dmub_aux_transfer_as
CVE-2026-64222 7.0 HIGH octeontx2-pf: avoid double free of pool->stack on AQ init failure
CVE-2026-64224 octeontx2-pf: fix double free in rvu_rep_rsrc_init()
CVE-2026-64227 ACPI: driver: Check ACPI_COMPANION() against NULL during probe
CVE-2026-64209 phy: qcom: qmp-usbc: Fix out-of-bounds array access in dp swing config
CVE-2026-64225 octeontx2-af: CGX: add bounds check to cgx_speed_mbps index

Showing top 20 of 48 CVEs. View all on vendor page &rarr; →

IV. Related Vulnerabilities

Same product: Linux
Same vendor: Linux

V. Comments for CVE-2026-64248

No comments yet

Leave a comment