{"cve":"CVE-2026-43087","nvd":{"published":"2026-05-06T10:16:21.963","modified":"2026-06-17T10:48:54.743","status":"Analyzed","description":"In the Linux kernel, the following vulnerability has been resolved:\n\npinctrl: mcp23s08: Disable all pin interrupts during probe\n\nA chip being probed may have the interrupt-on-change feature enabled on\nsome of its pins, for example after a reboot. This can cause the chip to\ngenerate interrupts for pins that don't have a registered nested handler,\nwhich leads to a kernel crash such as below:\n\n[    7.928897] Unable to handle kernel read from unreadable memory at virtual address 00000000000000ac\n[    7.932314] Mem abort info:\n[    7.935081]   ESR = 0x0000000096000004\n[    7.938808]   EC = 0x25: DABT (current EL), IL = 32 bits\n[    7.944094]   SET = 0, FnV = 0\n[    7.947127]   EA = 0, S1PTW = 0\n[    7.950247]   FSC = 0x04: level 0 translation fault\n[    7.955101] Data abort info:\n[    7.957961]   ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000\n[    7.963421]   CM = 0, WnR = 0, TnD = 0, TagAccess = 0\n[    7.968447]   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0\n[    7.973734] user pgtable: 4k pages, 48-bit VAs, pgdp=00000000089b7000\n[    7.980148] [00000000000000ac] pgd=0000000000000000, p4d=0000000000000000\n[    7.986913] Internal error: Oops: 0000000096000004 [#1]  SMP\n[    7.992545] Modules linked in:\n[    8.073678] CPU: 0 UID: 0 PID: 81 Comm: irq/18-4-0025 Not tainted 7.0.0-rc6-gd2b5a1f931c8-dirty #199\n[    8.073689] Hardware name: Khadas VIM3 (DT)\n[    8.073692] pstate: 604000c5 (nZCv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--)\n[    8.094639] pc : _raw_spin_lock_irq+0x40/0x80\n[    8.098970] lr : handle_nested_irq+0x2c/0x168\n[    8.098979] sp : ffff800082b2bd20\n[    8.106599] x29: ffff800082b2bd20 x28: ffff800080107920 x27: ffff800080104d88\n[    8.106611] x26: ffff000003298080 x25: 0000000000000001 x24: 000000000000ff00\n[    8.113707] x23: 0000000000000001 x22: 0000000000000000 x21: 000000000000000e\n[    8.120850] x20: 0000000000000000 x19: 00000000000000ac x18: 0000000000000000\n[    8.135046] x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000\n[    8.135062] x14: ffff800081567ea8 x13: ffffffffffffffff x12: 0000000000000000\n[    8.135070] x11: 00000000000000c0 x10: 0000000000000b60 x9 : ffff800080109e0c\n[    8.135078] x8 : 1fffe0000069dbc1 x7 : 0000000000000001 x6 : ffff0000034ede00\n[    8.135086] x5 : 0000000000000000 x4 : ffff0000034ede08 x3 : 0000000000000001\n[    8.163460] x2 : 0000000000000000 x1 : 0000000000000001 x0 : 00000000000000ac\n[    8.170560] Call trace:\n[    8.180094]  _raw_spin_lock_irq+0x40/0x80 (P)\n[    8.184443]  mcp23s08_irq+0x248/0x358\n[    8.184462]  irq_thread_fn+0x34/0xb8\n[    8.184470]  irq_thread+0x1a4/0x310\n[    8.195093]  kthread+0x13c/0x150\n[    8.198309]  ret_from_fork+0x10/0x20\n[    8.201850] Code: d65f03c0 d2800002 52800023 f9800011 (885ffc01)\n[    8.207931] ---[ end trace 0000000000000000 ]---\n\nThis issue has always been present, but has been latent until commit\n\"f9f4fda15e72\" (\"pinctrl: mcp23s08: init reg_defaults from HW at probe and\nswitch cache type\"), which correctly removed reg_defaults from the regmap\nand as a side effect changed the behavior of the interrupt handler so that\nthe real value of the MCP_GPINTEN register is now being read from the chip\ninstead of using a bogus 0 default value; a non-zero value for this\nregister can trigger the invocation of a nested handler which may not exist\n(yet).\nFix this issue by disabling all pin interrupts during initialization.","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/db5b8cecbdf479ad13156af750377e5b43853fab","https://git.kernel.org/stable/c/f8c3258541a0680a4ebc08b05b2bc5fdad3288a9"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:33:55.586217763+00:00"},"epss":{"cve":"CVE-2026-43087","score":0.00107,"percentile":0.01146,"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."]}