CVE-2026-43272

/* * PoC Concept for CVE-2026-43272 * This code demonstrates the logic flow leading to the vulnerability. * Triggering the specific validation failure requires precise interaction * with the ring buffer subsystem (e.g., via ftrace/perf). */ #include <linux/module.h> #include <linux/kernel.h> // Mocking the vulnerable logic scenario void vulnerable_logic(int validation_status) { void *head_page; // Uninitialized pointer int orig_head; // Simulate the validation function call if (validation_status != 0) { // Control jumps to error handling goto invalid; } // Normal initialization path head_page = kmalloc(PAGE_SIZE, GFP_KERNEL); // ... normal operations ... return; invalid: // Vulnerability: head_page is used here without initialization // if jumped directly from the check above. printk(KERN_INFO "Accessing head_page: %p\n", head_page); } int init_module(void) { // Trigger the path vulnerable_logic(-1); return 0; } void cleanup_module(void) {} MODULE_LICENSE("GPL");

{"cve": {"id": "CVE-2026-43272", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "published": "2026-05-06T12:16:48.433", "lastModified": "2026-05-08T20:00:37.403", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nring-buffer: Fix possible dereference of uninitialized pointer\n\nThere is a pointer head_page in rb_meta_validate_events() which is not\ninitialized at the beginning of a function. This pointer can be dereferenced\nif there is a failure during reader page validation. In this case the control\nis passed to \"invalid\" label where the pointer is dereferenced in a loop.\n\nTo fix the issue initialize orig_head and head_page before calling\nrb_validate_buffer.\n\nFound by Linux Verification Center (linuxtesting.org) with SVACE."}], "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": "6.12", "versionEndExcluding": "6.18.16", "matchCriteriaId": "932FBBB4-5FA7-4471-8493-E2DB77FEE8E8"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.19", "versionEndExcluding": "6.19.6", "matchCriteriaId": "373EEEDA-FAA1-4FB4-B6ED-DB4DD99DBE67"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/bc77986f3cb7476637052edf2d87137fa39f153d", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/d9942396845fef2369478c157b26738fe07142f6", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/f1547779402c4cd67755c33616b7203baa88420b", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}]}}