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

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2025-21806— net: let net.core.dev_weight always be non-zero

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，该漏洞源于未正确处理net.core.dev_weight，可能导致警告。

AI Predicted 6.5 Difficulty: Moderate EPSS 0.23% · P13

Possible ATT&CK Techniques 1 AI

T1548.002 · Bypass User Account Control

Affected Version Matrix 18

VendorProduct Version RangeStatus
Linux Linux e3876605450979fe52a1a03e7eb78a89bf59e76a< d0e0f9c8218826926d7692980c98236d9f21fd3c affected
e3876605450979fe52a1a03e7eb78a89bf59e76a< c337c08819a4ec49edfdcd8fc46fbee120d8a5b2 affected
e3876605450979fe52a1a03e7eb78a89bf59e76a< 0e2f1d93d287d544d26f8ff293ea820a8079b9f8 affected
e3876605450979fe52a1a03e7eb78a89bf59e76a< 5860abbf15eeb61838b5e32e721ba67b0aa84450 affected
e3876605450979fe52a1a03e7eb78a89bf59e76a< 6ce38b5a6a49e65bad163162a54cb3f104c40b48 affected
e3876605450979fe52a1a03e7eb78a89bf59e76a< 33e2168788f8fb5cb8bd4f36cb1ef37d1d34dada affected
e3876605450979fe52a1a03e7eb78a89bf59e76a< 1489824e5226a26841c70639ebd2d1aed390764b affected
e3876605450979fe52a1a03e7eb78a89bf59e76a< d1f9f79fa2af8e3b45cffdeef66e05833480148a affected
… +10 more rows
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2025-21806

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Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.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
net: let net.core.dev_weight always be non-zero
Source: CVE Program / CVE List V5
Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: net: let net.core.dev_weight always be non-zero The following problem was encountered during stability test: (NULL net_device): NAPI poll function process_backlog+0x0/0x530 \ returned 1, exceeding its budget of 0. ------------[ cut here ]------------ list_add double add: new=ffff88905f746f48, prev=ffff88905f746f48, \ next=ffff88905f746e40. WARNING: CPU: 18 PID: 5462 at lib/list_debug.c:35 \ __list_add_valid_or_report+0xf3/0x130 CPU: 18 UID: 0 PID: 5462 Comm: ping Kdump: loaded Not tainted 6.13.0-rc7+ RIP: 0010:__list_add_valid_or_report+0xf3/0x130 Call Trace: ? __warn+0xcd/0x250 ? __list_add_valid_or_report+0xf3/0x130 enqueue_to_backlog+0x923/0x1070 netif_rx_internal+0x92/0x2b0 __netif_rx+0x15/0x170 loopback_xmit+0x2ef/0x450 dev_hard_start_xmit+0x103/0x490 __dev_queue_xmit+0xeac/0x1950 ip_finish_output2+0x6cc/0x1620 ip_output+0x161/0x270 ip_push_pending_frames+0x155/0x1a0 raw_sendmsg+0xe13/0x1550 __sys_sendto+0x3bf/0x4e0 __x64_sys_sendto+0xdc/0x1b0 do_syscall_64+0x5b/0x170 entry_SYSCALL_64_after_hwframe+0x76/0x7e The reproduction command is as follows: sysctl -w net.core.dev_weight=0 ping 127.0.0.1 This is because when the napi's weight is set to 0, process_backlog() may return 0 and clear the NAPI_STATE_SCHED bit of napi->state, causing this napi to be re-polled in net_rx_action() until __do_softirq() times out. Since the NAPI_STATE_SCHED bit has been cleared, napi_schedule_rps() can be retriggered in enqueue_to_backlog(), causing this issue. Making the napi's weight always non-zero solves this problem. Triggering this issue requires system-wide admin (setting is not namespaced).
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，该漏洞源于未正确处理net.core.dev_weight，可能导致警告。
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 e3876605450979fe52a1a03e7eb78a89bf59e76a ~ d0e0f9c8218826926d7692980c98236d9f21fd3c -
Linux Linux 2.6.12 -

II. Public POCs for CVE-2025-21806

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

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2025-21806

请登录查看更多情报信息。

Patches & Fixes for CVE-2025-21806 (5)

Other References for CVE-2025-21806 (3)

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-2025-21765 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-2025-21762 8.1 HIGH arp: use RCU protection in arp_xmit()
CVE-2024-58010 7.8 HIGH binfmt_flat: Fix integer overflow bug on 32 bit systems
CVE-2024-58008 7.8 HIGH KEYS: trusted: dcp: fix improper sg use with CONFIG_VMAP_STACK=y
CVE-2025-21764 7.8 HIGH ndisc: use RCU protection in ndisc_alloc_skb()
CVE-2025-21791 7.8 HIGH vrf: use RCU protection in l3mdev_l3_out()
CVE-2025-21763 7.8 HIGH neighbour: use RCU protection in __neigh_notify()

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-2025-21806

No comments yet

Leave a comment