CVE-2026-43463

/* * Conceptual PoC for CVE-2026-43463 * This snippet simulates the missing IS_ERR() check logic. * Triggering this requires an environment where AFS is active * and memory allocation can be forced to fail during peer lookup. */ #include <linux/module.h> #include <linux/kernel.h> #include <rxrpc/rxrpc.h> // Simulated vulnerable scenario logic void vulnerable_afs_call(void) { struct rxrpc_peer *peer; // The function rxrpc_kernel_lookup_peer might return an error pointer peer = rxrpc_kernel_lookup_peer(...); // Vulnerability: Only checking for NULL, not IS_ERR(peer) if (peer == NULL) { pr_err("Peer is NULL\n"); return; } // If peer is an error pointer (e.g., -ENOMEM converted to pointer), // accessing it here causes a kernel crash (Oops/Panic). pr_info("Peer looked up: %p\n", peer); } // Note: Actual exploitation requires specific kernel conditions.

{"cve": {"id": "CVE-2026-43463", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "published": "2026-05-08T15:16:59.183", "lastModified": "2026-05-20T18:39:59.610", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nrxrpc, afs: Fix missing error pointer check after rxrpc_kernel_lookup_peer()\n\nrxrpc_kernel_lookup_peer() can also return error pointers in addition to\nNULL, so just checking for NULL is not sufficient.\n\nFix this by:\n\n (1) Changing rxrpc_kernel_lookup_peer() to return -ENOMEM rather than NULL\n on allocation failure.\n\n (2) Making the callers in afs use IS_ERR() and PTR_ERR() to pass on the\n error code returned."}], "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": "6.7.3", "versionEndExcluding": "6.8", "matchCriteriaId": "20F5F360-294D-4182-AC38-2F032FA57B3C"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.8", "versionEndExcluding": "6.18.19", "matchCriteriaId": "757358ED-CB5E-401C-9CA4-AB514EFDC61C"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.19", "versionEndExcluding": "6.19.9", "matchCriteriaId": "E825E7C3-FEAC-4FD3-8A81-78D7387948C9"}, {"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"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/4245a79003adf30e67f8e9060915bd05cb31d142", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/54331c5dcc6d97683d7ca2788e7ef9c9505e1477", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/d55fa7cd4b19ba91b34b307d769c149e56ad0a75", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}]}}