CVE-2025-39857
Status: ModifiedMedium (5.5)—
In the Linux kernel, the following vulnerability has been resolved:
net/smc: fix one NULL pointer dereference in smc_ib_is_sg_need_sync()
If the software RoCE device is used, ibdev->dma_device is a null pointer. As a result, the problem occurs. Null pointer detection is added to prevent problems.
Technical details traces, logs and code from the original report
BUG: kernel NULL pointer dereference, address: 00000000000002ec PGD 0 P4D 0 Oops: Oops: 0000 [#1] SMP PTI CPU: 28 UID: 0 PID: 343 Comm: kworker/28:1 Kdump: loaded Tainted: G OE 6.17.0-rc2+ #9 NONE Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014 Workqueue: smc_hs_wq smc_listen_work [smc] RIP: 0010:smc_ib_is_sg_need_sync+0x9e/0xd0 [smc] ... Call Trace: <TASK> smcr_buf_map_link+0x211/0x2a0 [smc] __smc_buf_create+0x522/0x970 [smc] smc_buf_create+0x3a/0x110 [smc] smc_find_rdma_v2_device_serv+0x18f/0x240 [smc] ? smc_vlan_by_tcpsk+0x7e/0xe0 [smc] smc_listen_find_device+0x1dd/0x2b0 [smc] smc_listen_work+0x30f/0x580 [smc] process_one_work+0x18c/0x340 worker_thread+0x242/0x360 kthread+0xe7/0x220 ret_from_fork+0x13a/0x160 ret_from_fork_asm+0x1a/0x30 </TASK>
CVSS
- Version: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- Base score: 5.5
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 0.31%
- Percentile among all scored CVEs: 21
- Score date: 10/6/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (2)
CWEs
- CWE-476
References
- https://git.kernel.org/stable/c/0cdf1fd8fc59d44a48c694324611136910301ef9
- https://git.kernel.org/stable/c/34f17cbe027050b8d5316ea1b6f9bd7c378e92de
- https://git.kernel.org/stable/c/ba1e9421cf1a8369d25c3832439702a015d6b5f9
- https://git.kernel.org/stable/c/eb929910bd4b4165920fa06a87b22cc6cae92e0e
- https://git.kernel.org/stable/c/f18d9b3abf9c6587372cc702f963a7592277ed56
- https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html
- https://cert-portal.siemens.com/productcert/html/ssa-032379.html
Raw JSON (NVD)
Show
{
"id": "CVE-2025-39857",
"cveTags": [],
"metrics": {
"cvssMetricV31": [
{
"type": "Secondary",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 7.5,
"attackVector": "NETWORK",
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"integrityImpact": "NONE",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "NONE",
"confidentialityImpact": "NONE"
},
"impactScore": 3.6,
"exploitabilityScore": 3.9
},
{
"type": "Primary",
"source": "nvd@nist.gov",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 5.5,
"attackVector": "LOCAL",
"baseSeverity": "MEDIUM",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
"integrityImpact": "NONE",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "LOW",
"confidentialityImpact": "NONE"
},
"impactScore": 3.6,
"exploitabilityScore": 1.8
}
]
},
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "0ef69e788411cba2af017db731a9fc62d255e9ac",
"lessThan": "0cdf1fd8fc59d44a48c694324611136910301ef9",
"versionType": "git"
},
{
"status": "affected",
"version": "0ef69e788411cba2af017db731a9fc62d255e9ac",
"lessThan": "f18d9b3abf9c6587372cc702f963a7592277ed56",
"versionType": "git"
},
{
"status": "affected",
"version": "0ef69e788411cba2af017db731a9fc62d255e9ac",
"lessThan": "eb929910bd4b4165920fa06a87b22cc6cae92e0e",
"versionType": "git"
},
{
"status": "affected",
"version": "0ef69e788411cba2af017db731a9fc62d255e9ac",
"lessThan": "34f17cbe027050b8d5316ea1b6f9bd7c378e92de",
"versionType": "git"
},
{
"status": "affected",
"version": "0ef69e788411cba2af017db731a9fc62d255e9ac",
"lessThan": "ba1e9421cf1a8369d25c3832439702a015d6b5f9",
"versionType": "git"
}
],
"programFiles": [
"net/smc/smc_ib.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "6.0"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "6.0",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.1.151",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.105",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.46",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.16.6",
"versionType": "semver",
"lessThanOrEqual": "6.16.*"
},
{
"status": "unaffected",
"version": "6.17",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/smc/smc_ib.c"
],
"defaultStatus": "affected"
}
]
},
{
"source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e",
"affectedData": [
{
"vendor": "Siemens",
"product": "SIMATIC CN 4100",
"versions": [
{
"status": "affected",
"version": "0",
"lessThan": "V5.0",
"versionType": "custom"
}
],
"defaultStatus": "unknown"
}
]
}
],
"published": "2025-09-19T16:15:44.650",
"references": [
{
"url": "https://git.kernel.org/stable/c/0cdf1fd8fc59d44a48c694324611136910301ef9",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/34f17cbe027050b8d5316ea1b6f9bd7c378e92de",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/ba1e9421cf1a8369d25c3832439702a015d6b5f9",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/eb929910bd4b4165920fa06a87b22cc6cae92e0e",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/f18d9b3abf9c6587372cc702f963a7592277ed56",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html",
"tags": [
"Mailing List",
"Third Party Advisory"
],
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "https://cert-portal.siemens.com/productcert/html/ssa-032379.html",
"source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"
}
],
"vulnStatus": "Modified",
"weaknesses": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"description": [
{
"lang": "en",
"value": "CWE-476"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/smc: fix one NULL pointer dereference in smc_ib_is_sg_need_sync()\n\nBUG: kernel NULL pointer dereference, address: 00000000000002ec\nPGD 0 P4D 0\nOops: Oops: 0000 [#1] SMP PTI\nCPU: 28 UID: 0 PID: 343 Comm: kworker/28:1 Kdump: loaded Tainted: G OE 6.17.0-rc2+ #9 NONE\nTainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE\nHardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014\nWorkqueue: smc_hs_wq smc_listen_work [smc]\nRIP: 0010:smc_ib_is_sg_need_sync+0x9e/0xd0 [smc]\n...\nCall Trace:\n <TASK>\n smcr_buf_map_link+0x211/0x2a0 [smc]\n __smc_buf_create+0x522/0x970 [smc]\n smc_buf_create+0x3a/0x110 [smc]\n smc_find_rdma_v2_device_serv+0x18f/0x240 [smc]\n ? smc_vlan_by_tcpsk+0x7e/0xe0 [smc]\n smc_listen_find_device+0x1dd/0x2b0 [smc]\n smc_listen_work+0x30f/0x580 [smc]\n process_one_work+0x18c/0x340\n worker_thread+0x242/0x360\n kthread+0xe7/0x220\n ret_from_fork+0x13a/0x160\n ret_from_fork_asm+0x1a/0x30\n </TASK>\n\nIf the software RoCE device is used, ibdev->dma_device is a null pointer.\nAs a result, the problem occurs. Null pointer detection is added to\nprevent problems."
}
],
"lastModified": "2026-07-30T06:23:51.340",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "8D1C4397-269E-4EBA-BB2D-D6356397B4D0",
"versionEndExcluding": "6.1.151",
"versionStartIncluding": "6.0"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "B9364B0C-6B18-422E-8254-73EF0E856875",
"versionEndExcluding": "6.6.105",
"versionStartIncluding": "6.2"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "F7E2B332-E920-4CAC-B400-288602DB6F16",
"versionEndExcluding": "6.12.46",
"versionStartIncluding": "6.7"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "548F104C-0F08-438B-9C97-64C903F0C678",
"versionEndExcluding": "6.16.6",
"versionStartIncluding": "6.13"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:6.17:rc1:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "327D22EF-390B-454C-BD31-2ED23C998A1C"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:6.17:rc2:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "C730CD9A-D969-4A8E-9522-162AAF7C0EE9"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:6.17:rc3:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "39982C4B-716E-4B2F-8196-FA301F47807D"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:6.17:rc4:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "340BEEA9-D70D-4290-B502-FBB1032353B1"
}
],
"operator": "OR"
}
]
},
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "FA6FEEC2-9F11-4643-8827-749718254FED"
}
],
"operator": "OR"
}
]
}
],
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}