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

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2026-93250— vxlan: mdb: Fix use-after-free in vxlan_mdb_flush()

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.

在 Linux 内核中，已修复以下漏洞： vxlan: mdb: 修复 vxlan_mdb_flush() 中的释放后使用（use-after-free）漏洞 使用 迭代 MDB（组播数据库）条目，该宏仅允许删除当前正在处理的条目。然而，与循环上方的注释相反，删除一个条目可能会触发删除另一个条目。 刷新 条目的远程地址时，也会删除为其源列表创建的 条目，因为这些条目在失去所有远程地址后将被移除。具体调用链如下： 这种被删除的 条目可能位于 条目之后的列表中，因为 返回已有条目时不会将其移动到列表头部。这种顺序是在添

CVSS 7.8 · High EPSS 0.16% · P4

Affected Version Matrix 12

VendorProduct Version RangeStatus
Linux Linux a3a48de5eade770e911d35291217bdd69ce04ef1< f8a9b988e7a7bc674e74e8c901794d792c35689e affected
a3a48de5eade770e911d35291217bdd69ce04ef1< c7dc26d06f90ca11bbd6114f6a62a67d038816c7 affected
a3a48de5eade770e911d35291217bdd69ce04ef1< 3e6b705bc162fc7257645725a7d2cf6c71250318 affected
a3a48de5eade770e911d35291217bdd69ce04ef1< f26400b325bdc2868e40612c4804c82cf8ba6275 affected
a3a48de5eade770e911d35291217bdd69ce04ef1< bc2dc66a6693a78f8c1e6ca2dbebd50f16e2c366 affected
6.4 affected
< 6.4 unaffected
6.6.157≤ 6.6.* unaffected
… +4 more rows
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-93250

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Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.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
vxlan: mdb: Fix use-after-free in vxlan_mdb_flush()
Source: CVE Program / CVE List V5
Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: vxlan: mdb: Fix use-after-free in vxlan_mdb_flush() vxlan_mdb_flush() iterates over the MDB entries using hlist_for_each_entry_safe(), which only tolerates the removal of the current entry. Contrary to the comment above the loop, the removal of an entry can trigger the removal of another entry. Flushing the remotes of a (*, G) entry also removes the (S, G) entries that were created for its source list, once they are left without remotes: vxlan_mdb_remotes_flush() -> vxlan_mdb_remote_del() -> vxlan_mdb_remote_srcs_del() -> vxlan_mdb_remote_src_del() -> vxlan_mdb_remote_src_fwd_del() -> __vxlan_mdb_del() -> vxlan_mdb_entry_put() Such an entry can be located after the (*, G) entry in the list, as vxlan_mdb_entry_get() returns an existing entry without moving it to the head of the list. This order is obtained by adding the (S, G) entry before the (*, G) entry, the latter with NLM_F_REPLACE, as the addition of the source otherwise fails with -EEXIST. The (S, G) entry is then the entry saved by hlist_for_each_entry_safe() and it is freed while the (*, G) entry is processed. The next iteration calls hlist_del() on it again, writing LIST_POISON1 to LIST_POISON2 [1]. Besides device deletion, the flush is also reachable from RTM_DELMDB with NLM_F_BULK. Fix by re-reading the next entry after the remotes were flushed. The current entry cannot be removed by this flush, as source lists can only be configured on (*, G) entries and the removed entries are (S, G) entries. It is therefore still linked and its next pointer reflects the removals. [1] BUG: KASAN: wild-memory-access in vxlan_mdb_entry_put.part.0+0x328/0x588 Write of size 8 at addr dead000000000122 by task ip/327 CPU: 3 UID: 1000 PID: 327 Comm: ip Not tainted 7.2.0-rc7 #2 PREEMPT Call trace: vxlan_mdb_entry_put.part.0+0x328/0x588 vxlan_mdb_flush+0x1d8/0x25c vxlan_mdb_fini+0x8c/0x100 vxlan_uninit+0x1c/0x7c unregister_netdevice_many_notify+0x954/0xd4c rtnl_dellink+0x210/0x530 rtnetlink_rcv_msg+0x434/0x4d0 netlink_rcv_skb+0xc4/0x204 rtnetlink_rcv+0x18/0x24 netlink_unicast+0x4b8/0x548 netlink_sendmsg+0x29c/0x560 ____sys_sendmsg+0x390/0x3ec ___sys_sendmsg+0x114/0x188 __sys_sendmsg+0xf0/0x178 __arm64_sys_sendmsg+0x48/0x60 invoke_syscall.constprop.0+0x58/0x180 el0_svc_common.constprop.0+0x74/0x140 do_el0_svc+0x30/0x40 el0_svc+0x38/0x98 el0t_64_sync_handler+0xa0/0xe4 el0t_64_sync+0x198/0x19c
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Source: CVE Program / CVE List V5
Vulnerability Type
N/A
Source: CVE Program / CVE List V5

Affected Products

Vendor Product Affected Versions CPE Subscribe
Linux Linux a3a48de5eade770e911d35291217bdd69ce04ef1 ~ f8a9b988e7a7bc674e74e8c901794d792c35689e -
Linux Linux 6.4 -

II. Public POCs for CVE-2026-93250

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

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2026-93250

请登录查看更多情报信息。

Patches & Fixes for CVE-2026-93250 (5)

Same Patch Batch · Linux · 2026-09-24 · 234 CVEs total

CVE-2026-93207 9.8 CRITICAL SUNRPC: Zero rpc_gss_wire_cred at svcauth_gss_decode_credbody() entry
CVE-2026-97413 9.8 CRITICAL RDMA/rtrs-srv: Fix integer underflow in process_read and process_write
CVE-2026-93228 9.1 CRITICAL svcrdma: Reject Write/Reply chunks with segcount 0
CVE-2026-93793 8.8 HIGH wifi: iwlwifi: mvm: validate TX_CMD response layout
CVE-2026-93799 8.8 HIGH wifi: iwlwifi: mvm: validate sta_id in BA window status notif
CVE-2026-93790 8.8 HIGH wifi: iwlwifi: mvm: fix out-of-bounds tid_data access in BA notif
CVE-2026-93806 8.8 HIGH wifi: cfg80211: validate assoc response length before status and IE access
CVE-2026-97442 8.8 HIGH wifi: ath11k: fix invalid data access in ath11k_dp_rx_h_undecap_nwifi
CVE-2026-97509 8.8 HIGH thunderbolt: Keep XDomain reference during the lifetime of a service
CVE-2026-97409 8.8 HIGH nvme-fc: Do not cancel requests in io target before it is initialized
CVE-2026-93280 8.8 HIGH greybus: audio: bound the topology section sizes against the fetched size
CVE-2026-93284 8.8 HIGH drm/pagemap: dma-unmap pages before handling migration errors
CVE-2026-97451 8.4 HIGH ACPICA: Fix integer overflow in acpi_ex_opcode_3A_1T_1R() (mid_op)
CVE-2026-97455 8.4 HIGH ACPICA: Fix use-after-free in acpi_ds_terminate_control_method()
CVE-2026-97452 8.4 HIGH ACPICA: Prevent adding invalid references
CVE-2026-97450 8.4 HIGH ACPICA: validate handler object type in two places
CVE-2026-93827 8.4 HIGH virtio-fs: avoid double-free on failed queue setup
CVE-2026-97433 8.2 HIGH nvme: validate FDP configuration descriptor sizes
CVE-2026-93787 8.1 HIGH smb: client: bound dirent name against end of SMB response in cifs_filldir
CVE-2026-93786 8.1 HIGH ksmbd: preserve VFS inherited POSIX ACL mask

Showing top 20 of 234 CVEs. View all on vendor page &rarr; →

IV. Related Vulnerabilities

Same product: Linux
Same vendor: Linux

V. Comments for CVE-2026-93250

No comments yet

Leave a comment