{"cve":"CVE-2026-53051","nvd":{"published":"2026-06-24T17:17:17.083","modified":"2026-07-21T17:23:46.997","status":"Analyzed","description":"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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":[],"references":["https://git.kernel.org/stable/c/010983063a806720b45778d191335f8ea864fea3","https://git.kernel.org/stable/c/34b3eef48d980cd37b876e128bbf314f69fb5d70","https://git.kernel.org/stable/c/b059a41bdd5b202b2b9d7708403fb43c69689e53","https://git.kernel.org/stable/c/ce899f9c019591b73ef84b9afa332ed53beece25"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:41:17.107060303+00:00"},"epss":{"cve":"CVE-2026-53051","score":0.00162,"percentile":0.05344,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}