CVE-2025-39850 (GCVE-0-2025-39850)
Vulnerability from cvelistv5 – Published: 2025-09-19 15:26 – Updated: 2026-05-11 21:37
VLAI
EPSS
VEX
Title
vxlan: Fix NPD in {arp,neigh}_reduce() when using nexthop objects
Summary
In the Linux kernel, the following vulnerability has been resolved:
vxlan: Fix NPD in {arp,neigh}_reduce() when using nexthop objects
When the "proxy" option is enabled on a VXLAN device, the device will
suppress ARP requests and IPv6 Neighbor Solicitation messages if it is
able to reply on behalf of the remote host. That is, if a matching and
valid neighbor entry is configured on the VXLAN device whose MAC address
is not behind the "any" remote (0.0.0.0 / ::).
The code currently assumes that the FDB entry for the neighbor's MAC
address points to a valid remote destination, but this is incorrect if
the entry is associated with an FDB nexthop group. This can result in a
NPD [1][3] which can be reproduced using [2][4].
Fix by checking that the remote destination exists before dereferencing
it.
[1]
BUG: kernel NULL pointer dereference, address: 0000000000000000
[...]
CPU: 4 UID: 0 PID: 365 Comm: arping Not tainted 6.17.0-rc2-virtme-g2a89cb21162c #2 PREEMPT(voluntary)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.17.0-4.fc41 04/01/2014
RIP: 0010:vxlan_xmit+0xb58/0x15f0
[...]
Call Trace:
<TASK>
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 nexthop add id 1 via 192.0.2.2 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 4789 proxy
ip neigh add 192.0.2.3 lladdr 00:11:22:33:44:55 nud perm dev vx0
bridge fdb add 00:11:22:33:44:55 dev vx0 self static nhid 10
arping -b -c 1 -s 192.0.2.1 -I vx0 192.0.2.3
[3]
BUG: kernel NULL pointer dereference, address: 0000000000000000
[...]
CPU: 13 UID: 0 PID: 372 Comm: ndisc6 Not tainted 6.17.0-rc2-virtmne-g6ee90cb26014 #3 PREEMPT(voluntary)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1v996), BIOS 1.17.0-4.fc41 04/01/2x014
RIP: 0010:vxlan_xmit+0x803/0x1600
[...]
Call Trace:
<TASK>
dev_hard_start_xmit+0x5d/0x1c0
__dev_queue_xmit+0x246/0xfd0
ip6_finish_output2+0x210/0x6c0
ip6_finish_output+0x1af/0x2b0
ip6_mr_output+0x92/0x3e0
ip6_send_skb+0x30/0x90
rawv6_sendmsg+0xe6e/0x12e0
__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
RIP: 0033:0x7f383422ec77
[4]
#!/bin/bash
ip address add 2001:db8:1::1/128 dev lo
ip nexthop add id 1 via 2001:db8:1::1 fdb
ip nexthop add id 10 group 1 fdb
ip link add name vx0 up type vxlan id 10010 local 2001:db8:1::1 dstport 4789 proxy
ip neigh add 2001:db8:1::3 lladdr 00:11:22:33:44:55 nud perm dev vx0
bridge fdb add 00:11:22:33:44:55 dev vx0 self static nhid 10
ndisc6 -r 1 -s 2001:db8:1::1 -w 1 2001:db8:1::3 vx0
Severity
5.5 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-01-14 19:20 UTC
CWE
- CWE-476 - NULL Pointer Dereference
Assigner
References
Impacted products
2 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Linux | Linux |
Affected:
1274e1cc42264d4e629841e4f182795cb0becfd2 , < e211e3f4199ac829bd493632efcd131d337cba9d
(git)
Affected: 1274e1cc42264d4e629841e4f182795cb0becfd2 , < 8cfa0f076842f9b3b4eb52ae0e41d16e25cbf8fa (git) Affected: 1274e1cc42264d4e629841e4f182795cb0becfd2 , < 1f5d2fd1ca04a23c18b1bde9a43ce2fa2ffa1bce (git) |
guessed | |
| Linux | Linux |
Affected:
5.8
Unaffected: 0 , < 5.8 (semver) Unaffected: 6.12.46 , ≤ 6.12.* (semver) Unaffected: 6.16.6 , ≤ 6.16.* (semver) Unaffected: 6.17 , ≤ * (original_commit_for_fix) |
guessed |
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"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvxlan: Fix NPD in {arp,neigh}_reduce() when using nexthop objects\n\nWhen the \"proxy\" option is enabled on a VXLAN device, the device will\nsuppress ARP requests and IPv6 Neighbor Solicitation messages if it is\nable to reply on behalf of the remote host. That is, if a matching and\nvalid neighbor entry is configured on the VXLAN device whose MAC address\nis not behind the \"any\" remote (0.0.0.0 / ::).\n\nThe code currently assumes that the FDB entry for the neighbor\u0027s MAC\naddress points to a valid remote destination, but this is incorrect if\nthe entry is associated with an FDB nexthop group. This can result in a\nNPD [1][3] which can be reproduced using [2][4].\n\nFix by checking that the remote destination exists before dereferencing\nit.\n\n[1]\nBUG: kernel NULL pointer dereference, address: 0000000000000000\n[...]\nCPU: 4 UID: 0 PID: 365 Comm: arping Not tainted 6.17.0-rc2-virtme-g2a89cb21162c #2 PREEMPT(voluntary)\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.17.0-4.fc41 04/01/2014\nRIP: 0010:vxlan_xmit+0xb58/0x15f0\n[...]\nCall Trace:\n \u003cTASK\u003e\n dev_hard_start_xmit+0x5d/0x1c0\n __dev_queue_xmit+0x246/0xfd0\n packet_sendmsg+0x113a/0x1850\n __sock_sendmsg+0x38/0x70\n __sys_sendto+0x126/0x180\n __x64_sys_sendto+0x24/0x30\n do_syscall_64+0xa4/0x260\n entry_SYSCALL_64_after_hwframe+0x4b/0x53\n\n[2]\n #!/bin/bash\n\n ip address add 192.0.2.1/32 dev lo\n\n ip nexthop add id 1 via 192.0.2.2 fdb\n ip nexthop add id 10 group 1 fdb\n\n ip link add name vx0 up type vxlan id 10010 local 192.0.2.1 dstport 4789 proxy\n\n ip neigh add 192.0.2.3 lladdr 00:11:22:33:44:55 nud perm dev vx0\n\n bridge fdb add 00:11:22:33:44:55 dev vx0 self static nhid 10\n\n arping -b -c 1 -s 192.0.2.1 -I vx0 192.0.2.3\n\n[3]\nBUG: kernel NULL pointer dereference, address: 0000000000000000\n[...]\nCPU: 13 UID: 0 PID: 372 Comm: ndisc6 Not tainted 6.17.0-rc2-virtmne-g6ee90cb26014 #3 PREEMPT(voluntary)\nHardware name: QEMU Standard PC (i440FX + PIIX, 1v996), BIOS 1.17.0-4.fc41 04/01/2x014\nRIP: 0010:vxlan_xmit+0x803/0x1600\n[...]\nCall Trace:\n \u003cTASK\u003e\n dev_hard_start_xmit+0x5d/0x1c0\n __dev_queue_xmit+0x246/0xfd0\n ip6_finish_output2+0x210/0x6c0\n ip6_finish_output+0x1af/0x2b0\n ip6_mr_output+0x92/0x3e0\n ip6_send_skb+0x30/0x90\n rawv6_sendmsg+0xe6e/0x12e0\n __sock_sendmsg+0x38/0x70\n __sys_sendto+0x126/0x180\n __x64_sys_sendto+0x24/0x30\n do_syscall_64+0xa4/0x260\n entry_SYSCALL_64_after_hwframe+0x4b/0x53\nRIP: 0033:0x7f383422ec77\n\n[4]\n #!/bin/bash\n\n ip address add 2001:db8:1::1/128 dev lo\n\n ip nexthop add id 1 via 2001:db8:1::1 fdb\n ip nexthop add id 10 group 1 fdb\n\n ip link add name vx0 up type vxlan id 10010 local 2001:db8:1::1 dstport 4789 proxy\n\n ip neigh add 2001:db8:1::3 lladdr 00:11:22:33:44:55 nud perm dev vx0\n\n bridge fdb add 00:11:22:33:44:55 dev vx0 self static nhid 10\n\n ndisc6 -r 1 -s 2001:db8:1::1 -w 1 2001:db8:1::3 vx0"
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"initial_release_date": "2025-09-21T01:02:47.000Z",
"product_status:known_affected": "23",
"source": "Microsoft CSAF VEX",
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"title": "vxlan: Fix NPD in {arp,neigh}_reduce() when using nexthop objects",
"url": "https://msrc.microsoft.com/csaf/vex/2025/msrc_cve-2025-39850.json",
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"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvxlan: Fix NPD in {arp,neigh}_reduce() when using nexthop objects\n\nWhen the \"proxy\" option is enabled on a VXLAN device, the device will\nsuppress ARP requests and IPv6 Neighbor Solicitation messages if it is\nable to reply on behalf of the remote host. That is, if a matching and\nvalid neighbor entry is configured on the VXLAN device whose MAC address\nis not behind the \"any\" remote (0.0.0.0 / ::).\n\nThe code currently assumes that the FDB entry for the neighbor\u0027s MAC\naddress points to a valid remote destination, but this is incorrect if\nthe entry is associated with an FDB nexthop group. This can result in a\nNPD [1][3] which can be reproduced using [2][4].\n\nFix by checking that the remote destination exists before dereferencing\nit.\n\n[1]\nBUG: kernel NULL pointer dereference, address: 0000000000000000\n[...]\nCPU: 4 UID: 0 PID: 365 Comm: arping Not tainted 6.17.0-rc2-virtme-g2a89cb21162c #2 PREEMPT(voluntary)\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.17.0-4.fc41 04/01/2014\nRIP: 0010:vxlan_xmit+0xb58/0x15f0\n[...]\nCall Trace:\n \u003cTASK\u003e\n dev_hard_start_xmit+0x5d/0x1c0\n __dev_queue_xmit+0x246/0xfd0\n packet_sendmsg+0x113a/0x1850\n __sock_sendmsg+0x38/0x70\n __sys_sendto+0x126/0x180\n __x64_sys_sendto+0x24/0x30\n do_syscall_64+0xa4/0x260\n entry_SYSCALL_64_after_hwframe+0x4b/0x53\n\n[2]\n #!/bin/bash\n\n ip address add 192.0.2.1/32 dev lo\n\n ip nexthop add id 1 via 192.0.2.2 fdb\n ip nexthop add id 10 group 1 fdb\n\n ip link add name vx0 up type vxlan id 10010 local 192.0.2.1 dstport 4789 proxy\n\n ip neigh add 192.0.2.3 lladdr 00:11:22:33:44:55 nud perm dev vx0\n\n bridge fdb add 00:11:22:33:44:55 dev vx0 self static nhid 10\n\n arping -b -c 1 -s 192.0.2.1 -I vx0 192.0.2.3\n\n[3]\nBUG: kernel NULL pointer dereference, address: 0000000000000000\n[...]\nCPU: 13 UID: 0 PID: 372 Comm: ndisc6 Not tainted 6.17.0-rc2-virtmne-g6ee90cb26014 #3 PREEMPT(voluntary)\nHardware name: QEMU Standard PC (i440FX + PIIX, 1v996), BIOS 1.17.0-4.fc41 04/01/2x014\nRIP: 0010:vxlan_xmit+0x803/0x1600\n[...]\nCall Trace:\n \u003cTASK\u003e\n dev_hard_start_xmit+0x5d/0x1c0\n __dev_queue_xmit+0x246/0xfd0\n ip6_finish_output2+0x210/0x6c0\n ip6_finish_output+0x1af/0x2b0\n ip6_mr_output+0x92/0x3e0\n ip6_send_skb+0x30/0x90\n rawv6_sendmsg+0xe6e/0x12e0\n __sock_sendmsg+0x38/0x70\n __sys_sendto+0x126/0x180\n __x64_sys_sendto+0x24/0x30\n do_syscall_64+0xa4/0x260\n entry_SYSCALL_64_after_hwframe+0x4b/0x53\nRIP: 0033:0x7f383422ec77\n\n[4]\n #!/bin/bash\n\n ip address add 2001:db8:1::1/128 dev lo\n\n ip nexthop add id 1 via 2001:db8:1::1 fdb\n ip nexthop add id 10 group 1 fdb\n\n ip link add name vx0 up type vxlan id 10010 local 2001:db8:1::1 dstport 4789 proxy\n\n ip neigh add 2001:db8:1::3 lladdr 00:11:22:33:44:55 nud perm dev vx0\n\n bridge fdb add 00:11:22:33:44:55 dev vx0 self static nhid 10\n\n ndisc6 -r 1 -s 2001:db8:1::1 -w 1 2001:db8:1::3 vx0"
}
],
"id": "CVE-2025-39850",
"lastModified": "2026-06-17T09:18:37.360",
"metrics": {
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"baseSeverity": "MEDIUM",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"privilegesRequired": "LOW",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
"version": "3.1"
},
"exploitabilityScore": 1.8,
"impactScore": 3.6,
"source": "nvd@nist.gov",
"type": "Primary"
},
{
"cvssData": {
"attackComplexity": "LOW",
"attackVector": "LOCAL",
"availabilityImpact": "HIGH",
"baseScore": 5.5,
"baseSeverity": "MEDIUM",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"privilegesRequired": "LOW",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
"version": "3.1"
},
"exploitabilityScore": 1.8,
"impactScore": 3.6,
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"type": "Secondary"
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2025-39850",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-01-14T19:20:51.126279Z",
"version": "2.0.3"
}
}
]
},
"published": "2025-09-19T16:15:43.873",
"references": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/1f5d2fd1ca04a23c18b1bde9a43ce2fa2ffa1bce"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/8cfa0f076842f9b3b4eb52ae0e41d16e25cbf8fa"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/e211e3f4199ac829bd493632efcd131d337cba9d"
}
],
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"vulnStatus": "Modified",
"weaknesses": [
{
"description": [
{
"lang": "en",
"value": "CWE-476"
}
],
"source": "nvd@nist.gov",
"type": "Primary"
},
{
"description": [
{
"lang": "en",
"value": "CWE-476"
}
],
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"type": "Secondary"
}
]
}
},
"redhat_vex": {
"aggregate_severity": "Moderate",
"current_release_date": "2026-06-30T01:23:28+00:00",
"cve": "CVE-2025-39850",
"id": "CVE-2025-39850",
"initial_release_date": "2025-09-19T00:00:00+00:00",
"product_status:known_affected": "184",
"product_status:known_not_affected": "90",
"source": "Red Hat CSAF VEX",
"status": "final",
"title": "kernel: vxlan: Fix NPD in {arp,neigh}_reduce() when using nexthop objects",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-39850.json",
"version": "3"
},
"vulnrichment": {
"containers": {
"adp": [
{
"metrics": [
{
"cvssV3_1": {
"attackComplexity": "LOW",
"attackVector": "LOCAL",
"availabilityImpact": "HIGH",
"baseScore": 5.5,
"baseSeverity": "MEDIUM",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"privilegesRequired": "LOW",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
"version": "3.1"
}
},
{
"other": {
"content": {
"id": "CVE-2025-39850",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "no"
},
{
"Technical Impact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-01-14T19:20:51.126279Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"problemTypes": [
{
"descriptions": [
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"cweId": "CWE-476",
"description": "CWE-476 NULL Pointer Dereference",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-01-14T19:20:46.105Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"drivers/net/vxlan/vxlan_core.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
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"lessThan": "e211e3f4199ac829bd493632efcd131d337cba9d",
"status": "affected",
"version": "1274e1cc42264d4e629841e4f182795cb0becfd2",
"versionType": "git"
},
{
"lessThan": "8cfa0f076842f9b3b4eb52ae0e41d16e25cbf8fa",
"status": "affected",
"version": "1274e1cc42264d4e629841e4f182795cb0becfd2",
"versionType": "git"
},
{
"lessThan": "1f5d2fd1ca04a23c18b1bde9a43ce2fa2ffa1bce",
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"product": "Linux",
"programFiles": [
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],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
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"status": "affected",
"version": "5.8"
},
{
"lessThan": "5.8",
"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.12.*",
"status": "unaffected",
"version": "6.12.46",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.16.*",
"status": "unaffected",
"version": "6.16.6",
"versionType": "semver"
},
{
"lessThanOrEqual": "*",
"status": "unaffected",
"version": "6.17",
"versionType": "original_commit_for_fix"
}
]
}
],
"cpeApplicability": [
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"nodes": [
{
"cpeMatch": [
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"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.12.46",
"versionStartIncluding": "5.8",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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}
],
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"descriptions": [
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"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvxlan: Fix NPD in {arp,neigh}_reduce() when using nexthop objects\n\nWhen the \"proxy\" option is enabled on a VXLAN device, the device will\nsuppress ARP requests and IPv6 Neighbor Solicitation messages if it is\nable to reply on behalf of the remote host. That is, if a matching and\nvalid neighbor entry is configured on the VXLAN device whose MAC address\nis not behind the \"any\" remote (0.0.0.0 / ::).\n\nThe code currently assumes that the FDB entry for the neighbor\u0027s MAC\naddress points to a valid remote destination, but this is incorrect if\nthe entry is associated with an FDB nexthop group. This can result in a\nNPD [1][3] which can be reproduced using [2][4].\n\nFix by checking that the remote destination exists before dereferencing\nit.\n\n[1]\nBUG: kernel NULL pointer dereference, address: 0000000000000000\n[...]\nCPU: 4 UID: 0 PID: 365 Comm: arping Not tainted 6.17.0-rc2-virtme-g2a89cb21162c #2 PREEMPT(voluntary)\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.17.0-4.fc41 04/01/2014\nRIP: 0010:vxlan_xmit+0xb58/0x15f0\n[...]\nCall Trace:\n \u003cTASK\u003e\n dev_hard_start_xmit+0x5d/0x1c0\n __dev_queue_xmit+0x246/0xfd0\n packet_sendmsg+0x113a/0x1850\n __sock_sendmsg+0x38/0x70\n __sys_sendto+0x126/0x180\n __x64_sys_sendto+0x24/0x30\n do_syscall_64+0xa4/0x260\n entry_SYSCALL_64_after_hwframe+0x4b/0x53\n\n[2]\n #!/bin/bash\n\n ip address add 192.0.2.1/32 dev lo\n\n ip nexthop add id 1 via 192.0.2.2 fdb\n ip nexthop add id 10 group 1 fdb\n\n ip link add name vx0 up type vxlan id 10010 local 192.0.2.1 dstport 4789 proxy\n\n ip neigh add 192.0.2.3 lladdr 00:11:22:33:44:55 nud perm dev vx0\n\n bridge fdb add 00:11:22:33:44:55 dev vx0 self static nhid 10\n\n arping -b -c 1 -s 192.0.2.1 -I vx0 192.0.2.3\n\n[3]\nBUG: kernel NULL pointer dereference, address: 0000000000000000\n[...]\nCPU: 13 UID: 0 PID: 372 Comm: ndisc6 Not tainted 6.17.0-rc2-virtmne-g6ee90cb26014 #3 PREEMPT(voluntary)\nHardware name: QEMU Standard PC (i440FX + PIIX, 1v996), BIOS 1.17.0-4.fc41 04/01/2x014\nRIP: 0010:vxlan_xmit+0x803/0x1600\n[...]\nCall Trace:\n \u003cTASK\u003e\n dev_hard_start_xmit+0x5d/0x1c0\n __dev_queue_xmit+0x246/0xfd0\n ip6_finish_output2+0x210/0x6c0\n ip6_finish_output+0x1af/0x2b0\n ip6_mr_output+0x92/0x3e0\n ip6_send_skb+0x30/0x90\n rawv6_sendmsg+0xe6e/0x12e0\n __sock_sendmsg+0x38/0x70\n __sys_sendto+0x126/0x180\n __x64_sys_sendto+0x24/0x30\n do_syscall_64+0xa4/0x260\n entry_SYSCALL_64_after_hwframe+0x4b/0x53\nRIP: 0033:0x7f383422ec77\n\n[4]\n #!/bin/bash\n\n ip address add 2001:db8:1::1/128 dev lo\n\n ip nexthop add id 1 via 2001:db8:1::1 fdb\n ip nexthop add id 10 group 1 fdb\n\n ip link add name vx0 up type vxlan id 10010 local 2001:db8:1::1 dstport 4789 proxy\n\n ip neigh add 2001:db8:1::3 lladdr 00:11:22:33:44:55 nud perm dev vx0\n\n bridge fdb add 00:11:22:33:44:55 dev vx0 self static nhid 10\n\n ndisc6 -r 1 -s 2001:db8:1::1 -w 1 2001:db8:1::3 vx0"
}
],
"providerMetadata": {
"dateUpdated": "2025-09-29T06:01:01.501Z",
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"shortName": "Linux"
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"references": [
{
"url": "https://git.kernel.org/stable/c/e211e3f4199ac829bd493632efcd131d337cba9d"
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{
"url": "https://git.kernel.org/stable/c/8cfa0f076842f9b3b4eb52ae0e41d16e25cbf8fa"
},
{
"url": "https://git.kernel.org/stable/c/1f5d2fd1ca04a23c18b1bde9a43ce2fa2ffa1bce"
}
],
"title": "vxlan: Fix NPD in {arp,neigh}_reduce() when using nexthop objects",
"x_generator": {
"engine": "bippy-1.2.0"
}
}
},
"cveMetadata": {
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"assignerShortName": "Linux",
"cveId": "CVE-2025-39850",
"datePublished": "2025-09-19T15:26:22.803Z",
"dateReserved": "2025-04-16T07:20:57.142Z",
"dateUpdated": "2025-09-29T06:01:01.501Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.1"
}
}
}
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
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