CVE-2026-31749

/* * PoC Concept for CVE-2026-31749 * Triggering the null pointer dereference in ni_atmio16d driver. * This requires a system with the vulnerable kernel module loaded. */ #include <stdio.h> #include <stdlib.h> #include <fcntl.h> #include <unistd.h> #include <sys/ioctl.h> #define DEVICE_FILE "/dev/comedi0" int main() { int fd; printf("[*] Attempting to trigger vulnerability in ni_atmio16d...\n"); // Open the comedi device. If the attach fails during initialization // (e.g. due to missing hardware or manual trigger), // the detach logic will be called. fd = open(DEVICE_FILE, O_RDWR); if (fd < 0) { perror("[-] Failed to open device"); // In a real scenario, specific hardware emulation or forcing // the module to attach and fail is needed to reproduce the crash. return 1; } printf("[+] Device opened. Manipulating device to force failed attach state...\n"); // Specific IOCTLs or configuration steps that cause the driver // to enter the error handling path in atmio16d_attach // would go here. Once triggered, the kernel will panic // due to NULL pointer dereference in atmio16d_detach. close(fd); return 0; }

{"cve": {"id": "CVE-2026-31749", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "published": "2026-05-01T15:16:37.723", "lastModified": "2026-05-07T19:18:34.470", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncomedi: ni_atmio16d: Fix invalid clean-up after failed attach\n\nIf the driver's COMEDI \"attach\" handler function (`atmio16d_attach()`)\nreturns an error, the COMEDI core will call the driver's \"detach\"\nhandler function (`atmio16d_detach()`) to clean up. This calls\n`reset_atmio16d()` unconditionally, but depending on where the error\noccurred in the attach handler, the device may not have been\nsufficiently initialized to call `reset_atmio16d()`. It uses\n`dev->iobase` as the I/O port base address and `dev->private` as the\npointer to the COMEDI device's private data structure. `dev->iobase`\nmay still be set to its initial value of 0, which would result in\nundesired writes to low I/O port addresses. `dev->private` may still be\n`NULL`, which would result in null pointer dereferences.\n\nFix `atmio16d_detach()` by checking that `dev->private` is valid\n(non-null) before calling `reset_atmio16d()`. This implies that\n`dev->iobase` was set correctly since that is set up before\n`dev->private`."}], "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}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-476"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.30", "versionEndExcluding": "5.10.253", "matchCriteriaId": "14B74C0E-F4B9-41B2-B587-14056AC9B646"}, {"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": "6.6.134", "matchCriteriaId": "F56F925B-BAF8-4F4B-B62F-1496AF19A307"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.7", "versionEndExcluding": "6.12.81", "matchCriteriaId": "6EF80433-B33B-43C5-8E64-0FA7B8DCE1BC"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.13", "versionEndExcluding": "6.18.22", "matchCriteriaId": "C9DF8BCE-36D3-475D-9D21-19E4F02F9029"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.19", "versionEndExcluding": "6.19.12", "matchCriteriaId": "0A2B9540-02D5-41B4-B16A-82AF66FD4F36"}, {"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"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/101ab946b79ad83b36d5cfd47de587492a80acf0", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/3848ae00b1642e2c98ff8cbfd2d3b38c6f53b5c3", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/43c68a2c7cc35b7c2a83c285cb4ad3d472b8caa2", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/5d8d88c8c0eec230de8f1f60e0920a4337939a88", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, { ... 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