CVE-2026-53051
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: PCI: tegra194: Fix CBB timeout caused by DBI access before core power-on When PERST# is deasserted twice (assert -> deassert -> assert -> deassert), a CBB (Control Backbone) timeout occurs at DBI register offset 0x8bc (PCIE_MISC_CONTROL_1_OFF). This happens because pci_epc_deinit_notify() and dw_pcie_ep_cleanup() are called before reset_control_deassert() powers on the controller core. The call chain that causes the timeout: pex_ep_event_pex_rst_deassert() pci_epc_deinit_notify() pci_epf_test_epc_deinit() pci_epf_test_clear_bar() pci_epc_clear_bar() dw_pcie_ep_clear_bar() __dw_pcie_ep_reset_bar() dw_pcie_dbi_ro_wr_en() <- Accesses 0x8bc DBI register reset_control_deassert(pcie->core_rst) <- Core powered on HERE The DBI registers, including PCIE_MISC_CONTROL_1_OFF (0x8bc), are only accessible after the controller core is powered on via reset_control_deassert(pcie->core_rst). Accessing them before this point results in a CBB timeout because the hardware is not yet operational. Fix this by moving pci_epc_deinit_notify() and dw_pcie_ep_cleanup() to after reset_control_deassert(pcie->core_rst), ensuring the controller is fully powered on before any DBI register accesses occur.
Severity
MEDIUM
CVSS score
5.5
(v3.1)
Vulnerability status
Analyzed
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-06-24 17:17:17.083000
Last modified
2026-11-06 17:18:03.267000
View original CVE JSON
{
"id": "CVE-2026-53051",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-06-24T17:17:17.083",
"lastModified": "2026-11-06T17:18:03.267",
"vulnStatus": "Analyzed",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nPCI: tegra194: Fix CBB timeout caused by DBI access before core power-on\n\nWhen PERST# is deasserted twice (assert -> deassert -> assert -> deassert),\na CBB (Control Backbone) timeout occurs at DBI register offset 0x8bc\n(PCIE_MISC_CONTROL_1_OFF). This happens because pci_epc_deinit_notify()\nand dw_pcie_ep_cleanup() are called before reset_control_deassert() powers\non the controller core.\n\nThe call chain that causes the timeout:\n\n pex_ep_event_pex_rst_deassert()\n pci_epc_deinit_notify()\n pci_epf_test_epc_deinit()\n pci_epf_test_clear_bar()\n pci_epc_clear_bar()\n dw_pcie_ep_clear_bar()\n __dw_pcie_ep_reset_bar()\n dw_pcie_dbi_ro_wr_en() <- Accesses 0x8bc DBI register\n reset_control_deassert(pcie->core_rst) <- Core powered on HERE\n\nThe DBI registers, including PCIE_MISC_CONTROL_1_OFF (0x8bc), are only\naccessible after the controller core is powered on via\nreset_control_deassert(pcie->core_rst). Accessing them before this point\nresults in a CBB timeout because the hardware is not yet operational.\n\nFix this by moving pci_epc_deinit_notify() and dw_pcie_ep_cleanup() to\nafter reset_control_deassert(pcie->core_rst), ensuring the controller is\nfully powered on before any DBI register accesses occur."
}
],
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "unaffected",
"programFiles": [
"drivers/pci/controller/dwc/pcie-tegra194.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "72034050ccf4202cd6558b0afd2474f756ea3b9b",
"lessThan": "010983063a806720b45778d191335f8ea864fea3",
"versionType": "git",
"status": "affected"
},
{
"version": "40e2125381dc11379112485e3eefdd25c6df5375",
"lessThan": "b059a41bdd5b202b2b9d7708403fb43c69689e53",
"versionType": "git",
"status": "affected"
},
{
"version": "40e2125381dc11379112485e3eefdd25c6df5375",
"lessThan": "ce899f9c019591b73ef84b9afa332ed53beece25",
"versionType": "git",
"status": "affected"
},
{
"version": "40e2125381dc11379112485e3eefdd25c6df5375",
"lessThan": "34b3eef48d980cd37b876e128bbf314f69fb5d70",
"versionType": "git",
"status": "affected"
},
{
"version": "70212c2300971506e986d95000d2745529cac9d7",
"versionType": "git",
"status": "affected"
},
{
"version": "6.12.2",
"lessThan": "6.12.91",
"versionType": "semver",
"status": "affected"
},
{
"version": "6.11.11",
"lessThan": "6.12",
"versionType": "semver",
"status": "affected"
}
]
},
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "affected",
"programFiles": [
"drivers/pci/controller/dwc/pcie-tegra194.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "6.13",
"status": "affected"
},
{
"version": "0",
"lessThan": "6.13",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.12.91",
"lessThanOrEqual": "6.12.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.18.33",
"lessThanOrEqual": "6.18.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.0.10",
"lessThanOrEqual": "7.0.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.1",
"lessThanOrEqual": "*",
"versionType": "original_commit_for_fix",
"status": "unaffected"
}
]
}
]
}
],
"metrics": {
"cvssMetricV31": [
{
"source": "[email protected]",
"type": "Primary",
"cvssData": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
"baseScore": 5.5,
"baseSeverity": "MEDIUM",
"attackVector": "LOCAL",
"attackComplexity": "LOW",
"privilegesRequired": "LOW",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"availabilityImpact": "HIGH"
},
"exploitabilityScore": 1.8,
"impactScore": 3.6
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"timestamp": "2026-11-06T16:17:18.206478Z",
"id": "CVE-2026-53051",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "partial"
}
],
"role": "CISA Coordinator",
"version": "2.0.3"
}
}
]
},
"weaknesses": [
{
"source": "[email protected]",
"type": "Primary",
"description": [
{
"lang": "en",
"value": "NVD-CWE-noinfo"
}
]
}
],
"configurations": [
{
"nodes": [
{
"operator": "OR",
"negate": false,
"cpeMatch": [
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "6.11.11",
"versionEndExcluding": "6.12",
"matchCriteriaId": "4CBF5F6E-D446-4CAE-AAA4-413442319824"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "6.12.2",
"versionEndExcluding": "6.12.91",
"matchCriteriaId": "2DC91312-203C-41B3-ACD0-6722E77B72F4"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "6.13",
"versionEndExcluding": "6.18.33",
"matchCriteriaId": "96D99E49-380D-43AB-BDBA-25C3AD018A9C"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "6.19",
"versionEndExcluding": "7.0.10",
"matchCriteriaId": "A13475D2-59BF-4716-94B5-7C1D239A2CF4"
}
]
}
]
}
],
"references": [
{
"url": "https://git.kernel.org/stable/c/010983063a806720b45778d191335f8ea864fea3",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
]
},
{
"url": "https://git.kernel.org/stable/c/34b3eef48d980cd37b876e128bbf314f69fb5d70",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
]
},
{
"url": "https://git.kernel.org/stable/c/b059a41bdd5b202b2b9d7708403fb43c69689e53",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
]
},
{
"url": "https://git.kernel.org/stable/c/ce899f9c019591b73ef84b9afa332ed53beece25",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
]
}
]
}