{"id":"CVE-2026-72111","revision":"0e0a0ff1324c4742be00d76ff7abf099","records":[{"revision":"0e0a0ff1324c4742be00d76ff7abf099","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-72111","aliases":[],"title":"bpf: Reset register bounds before narrowing retval range in check_mem_access()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Reset register bounds before narrowing retval range in check_mem_access()\n\nWhen the BPF verifier processes a context load of an LSM hook return\nvalue, it calls __mark_reg_s32_range() to narrow the register to the\nhook's valid range. However, __mark_reg_s32_range() intersects the new\nrange with the register's existing bounds using max_t()/min_t() rather\nthan replacing them.\n\nIf the destination register carries stale bounds from a prior instruction\n(e.g. BPF_MOV64_IMM), the intersection can produce a range narrower than\nreality. The verifier then believes it knows the register's exact value,\nwhile at runtime the actual hook return value is loaded, creating a\nverifier/runtime mismatch that can be used to bypass BPF memory safety\nchecks.\n\nThe else branch already calls mark_reg_unknown() to reset register state\nbefore any narrowing. Apply the same reset in the is_retval path so\nstale bounds are cleared before __mark_reg_s32_range() intersects.","state":0,"publishedAt":"2026-08-15T05:52:52.538+00:00","modifiedAt":"2026-10-16T18:44:56.296+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"kernel/bpf/verifier.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"5d99e198be279045e6ecefe220f5c52f8ce9bfd5\",\n                            \"lessThan\": \"bde92f65042ec14389782dd223f706bf6b59ce5d\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"5d99e198be279045e6ecefe220f5c52f8ce9bfd5\",\n                            \"lessThan\": \"0993dc5fc619c0b25ab1310cb11d65e78351c0fe\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"5d99e198be279045e6ecefe220f5c52f8ce9bfd5\",\n                            \"lessThan\": \"5a55f9aecc08990940e70f0c7048a80850c5a16a\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"5d99e198be279045e6ecefe220f5c52f8ce9bfd5\",\n                            \"lessThan\": \"5e0b273e0a62cc04ec338c7b502797c66c2ed42a\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"1050727d83e70449991c29dd1cf29fe936a63da3\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"27ca3e20fe80be85a92b10064dfeb56cb2564b1c\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"6.10.13\",\n                            \"lessThan\": \"6.11\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.11.2\",\n                            \"lessThan\": \"6.12\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"semver\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"kernel/bpf/verifier.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"6.12\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"6.12\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.103\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.40\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.1.5\",\n                            \"lessThanOrEqual\": \"7.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","score":8.8,"severity":"HIGH"}],"references":["https://git.kernel.org/stable/c/bde92f65042ec14389782dd223f706bf6b59ce5d","https://git.kernel.org/stable/c/0993dc5fc619c0b25ab1310cb11d65e78351c0fe","https://git.kernel.org/stable/c/5a55f9aecc08990940e70f0c7048a80850c5a16a","https://git.kernel.org/stable/c/5e0b273e0a62cc04ec338c7b502797c66c2ed42a"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-72111","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-72111","identifiers":["CVE-2026-72111"]},"retained":false,"historicalAffected":[]}],"coverage":[]}