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

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2025-21767— clocksource: Use migrate_disable() to avoid calling get_random_u32() in atomic context

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基金会的开源操作系统Linux所使用的内核。 Linux kernel存在安全漏洞，该漏洞源于clocksource_verify_choose_cpus函数在原子上下文中调用get_random_u32，可能导致睡眠函数调用。

AI Predicted 5.5 Difficulty: Trivial EPSS 0.18% · P7

Possible ATT&CK Techniques 1 AI

T1496 · Resource Hijacking

Affected Version Matrix 21

VendorProduct Version RangeStatus
Linux Linux d9b40ebd448e437ffbc65f013836f98252279a82< d9c217fadfcff7a8df58567517d1e4253f3fd243 affected
7560c02bdffb7c52d1457fa551b9e745d4b9e754< 60f54f0d4ea530950549a8263e6fdd70a40490a4 affected
7560c02bdffb7c52d1457fa551b9e745d4b9e754< 852805b6cbdb69c298a8fc9fbe79994c95106e04 affected
7560c02bdffb7c52d1457fa551b9e745d4b9e754< 8783ceeee797d9aa9cfe150690fb9d0bac8cc459 affected
7560c02bdffb7c52d1457fa551b9e745d4b9e754< cc3d79e7c806cb57d71c28a4a35e7d7fb3265faa affected
7560c02bdffb7c52d1457fa551b9e745d4b9e754< 0fb534187d2355f6c8f995321e76d1ccd1262ac1 affected
7560c02bdffb7c52d1457fa551b9e745d4b9e754< 6bb05a33337b2c842373857b63de5c9bf1ae2a09 affected
193e14e68e907b2a7a936a7726accbaa4df25a4d affected
… +13 more rows
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2025-21767

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Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.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
clocksource: Use migrate_disable() to avoid calling get_random_u32() in atomic context
Source: CVE Program / CVE List V5
Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: clocksource: Use migrate_disable() to avoid calling get_random_u32() in atomic context The following bug report happened with a PREEMPT_RT kernel: BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:48 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 2012, name: kwatchdog preempt_count: 1, expected: 0 RCU nest depth: 0, expected: 0 get_random_u32+0x4f/0x110 clocksource_verify_choose_cpus+0xab/0x1a0 clocksource_verify_percpu.part.0+0x6b/0x330 clocksource_watchdog_kthread+0x193/0x1a0 It is due to the fact that clocksource_verify_choose_cpus() is invoked with preemption disabled. This function invokes get_random_u32() to obtain random numbers for choosing CPUs. The batched_entropy_32 local lock and/or the base_crng.lock spinlock in driver/char/random.c will be acquired during the call. In PREEMPT_RT kernel, they are both sleeping locks and so cannot be acquired in atomic context. Fix this problem by using migrate_disable() to allow smp_processor_id() to be reliably used without introducing atomic context. preempt_disable() is then called after clocksource_verify_choose_cpus() but before the clocksource measurement is being run to avoid introducing unexpected latency.
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基金会的开源操作系统Linux所使用的内核。 Linux kernel存在安全漏洞，该漏洞源于clocksource_verify_choose_cpus函数在原子上下文中调用get_random_u32，可能导致睡眠函数调用。
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 d9b40ebd448e437ffbc65f013836f98252279a82 ~ d9c217fadfcff7a8df58567517d1e4253f3fd243 -
Linux Linux 5.14 -

II. Public POCs for CVE-2025-21767

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

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2025-21767

请登录查看更多情报信息。

Patches & Fixes for CVE-2025-21767 (5)

Other References for CVE-2025-21767 (2)

Same Patch Batch · Linux · 2025-02-27 · 177 CVEs total

CVE-2025-21805 9.8 CRITICAL RDMA/rtrs: Add missing deinit() call
CVE-2025-21796 9.8 CRITICAL nfsd: clear acl_access/acl_default after releasing them
CVE-2025-21707 9.8 CRITICAL mptcp: consolidate suboption status
CVE-2025-21748 9.8 CRITICAL ksmbd: fix integer overflows on 32 bit systems
CVE-2024-58006 9.6 CRITICAL PCI: dwc: ep: Prevent changing BAR size/flags in pci_epc_set_bar()
CVE-2024-57999 8.8 HIGH powerpc/pseries/iommu: IOMMU incorrectly marks MMIO range in DDW
CVE-2025-21735 8.8 HIGH NFC: nci: Add bounds checking in nci_hci_create_pipe()
CVE-2024-57997 8.8 HIGH wifi: wcn36xx: fix channel survey memory allocation size
CVE-2024-57995 8.8 HIGH wifi: ath12k: fix read pointer after free in ath12k_mac_assign_vif_to_vdev()
CVE-2025-21710 8.2 HIGH tcp: correct handling of extreme memory squeeze
CVE-2025-21766 8.1 HIGH ipv4: use RCU protection in __ip_rt_update_pmtu()
CVE-2024-57973 8.1 HIGH rdma/cxgb4: Prevent potential integer overflow on 32bit
CVE-2025-21762 8.1 HIGH arp: use RCU protection in arp_xmit()
CVE-2025-21765 8.1 HIGH ipv6: use RCU protection in ip6_default_advmss()
CVE-2025-21760 8.1 HIGH ndisc: extend RCU protection in ndisc_send_skb()
CVE-2024-58013 7.8 HIGH Bluetooth: MGMT: Fix slab-use-after-free Read in mgmt_remove_adv_monitor_sync
CVE-2025-21763 7.8 HIGH neighbour: use RCU protection in __neigh_notify()
CVE-2024-58010 7.8 HIGH binfmt_flat: Fix integer overflow bug on 32 bit systems
CVE-2025-21764 7.8 HIGH ndisc: use RCU protection in ndisc_alloc_skb()
CVE-2025-21792 7.8 HIGH ax25: Fix refcount leak caused by setting SO_BINDTODEVICE sockopt

Showing top 20 of 177 CVEs. View all on vendor page &rarr; →

IV. Related Vulnerabilities

Same product: Linux
Same vendor: Linux

V. Comments for CVE-2025-21767

No comments yet

Leave a comment