CVE-2025-39851 (CNNVD-202509-3118)
中文标题:
Linux kernel 安全漏洞
英文标题:
vxlan: Fix NPD when refreshing an FDB entry with a nexthop object
漏洞描述
中文描述:
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指向FDB nexthop组的FDB条目，可能导致空指针取消引用。
英文描述:
In the Linux kernel, the following vulnerability has been resolved: vxlan: Fix NPD when refreshing an FDB entry with a nexthop object VXLAN FDB entries can point to either a remote destination or an FDB nexthop group. The latter is usually used in EVPN deployments where learning is disabled. However, when learning is enabled, an incoming packet might try to refresh an FDB entry that points to an FDB nexthop group and therefore does not have a remote. Such packets should be dropped, but they are only dropped after dereferencing the non-existent remote, resulting in a NPD [1] which can be reproduced using [2]. Fix by dropping such packets earlier. Remove the misleading comment from first_remote_rcu(). [1] BUG: kernel NULL pointer dereference, address: 0000000000000000 [...] CPU: 13 UID: 0 PID: 361 Comm: mausezahn Not tainted 6.17.0-rc1-virtme-g9f6b606b6b37 #1 PREEMPT(voluntary) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.17.0-4.fc41 04/01/2014 RIP: 0010:vxlan_snoop+0x98/0x1e0 [...] Call Trace: <TASK> vxlan_encap_bypass+0x209/0x240 encap_bypass_if_local+0xb1/0x100 vxlan_xmit_one+0x1375/0x17e0 vxlan_xmit+0x6b4/0x15f0 dev_hard_start_xmit+0x5d/0x1c0 __dev_queue_xmit+0x246/0xfd0 packet_sendmsg+0x113a/0x1850 __sock_sendmsg+0x38/0x70 __sys_sendto+0x126/0x180 __x64_sys_sendto+0x24/0x30 do_syscall_64+0xa4/0x260 entry_SYSCALL_64_after_hwframe+0x4b/0x53 [2] #!/bin/bash ip address add 192.0.2.1/32 dev lo ip address add 192.0.2.2/32 dev lo ip nexthop add id 1 via 192.0.2.3 fdb ip nexthop add id 10 group 1 fdb ip link add name vx0 up type vxlan id 10010 local 192.0.2.1 dstport 12345 localbypass ip link add name vx1 up type vxlan id 10020 local 192.0.2.2 dstport 54321 learning bridge fdb add 00:11:22:33:44:55 dev vx0 self static dst 192.0.2.2 port 54321 vni 10020 bridge fdb add 00:aa:bb:cc:dd:ee dev vx1 self static nhid 10 mausezahn vx0 -a 00:aa:bb:cc:dd:ee -b 00:11:22:33:44:55 -c 1 -q
CWE类型:
标签:
受影响产品
| 厂商 | 产品 | 版本 | 版本范围 | 平台 | CPE |
|---|---|---|---|---|---|
| Linux | Linux | - | < 4ff4f3104da6507e0f118c63c4560dfdeb59dce3 | - |
cpe:2.3:a:linux:linux:*:*:*:*:*:*:*:*
|
| Linux | Linux | 5.8 | - | - |
cpe:2.3:a:linux:linux:5.8:*:*:*:*:*:*:*
|
解决方案
中文解决方案:
英文解决方案:
临时解决方案:
CVSS评分详情
时间信息
利用信息
数据源详情
| 数据源 | 记录ID | 版本 | 提取时间 |
|---|---|---|---|
| CVE | cve_CVE-2025-39851 |
2025-11-11 15:23:19 | 2025-11-11 07:40:29 |
| NVD | nvd_CVE-2025-39851 |
2025-11-11 15:01:03 | 2025-11-11 07:48:18 |
| CNNVD | cnnvd_CNNVD-202509-3118 |
2025-11-11 15:12:58 | 2025-11-11 08:00:12 |
版本与语言
安全公告
变更历史
查看详细变更
- vulnerability_type: 未提取 -> 其他
- severity: SeverityLevel.MEDIUM -> SeverityLevel.UNKNOWN
- cvss_score: 未提取 -> 0.0
- cnnvd_id: 未提取 -> CNNVD-202509-3118
- data_sources: ['cve', 'nvd'] -> ['cnnvd', 'cve', 'nvd']
查看详细变更
- affected_products_count: 4 -> 2
- data_sources: ['cve'] -> ['cve', 'nvd']