CVE-2026-53243

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-53243", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-06-09T07:44:35.393Z", "datePublished": "2026-06-25T08:39:37.794Z", "dateUpdated": "2026-06-25T08:39:37.794Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-06-25T08:39:37.794Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nrseq: Fix using an uninitialized stack variable in rseq_exit_user_update()\n\nThere is an bug in which an uninitialized stack variable is used in\nrseq_exit_user_update() as reported by syzbot:\n\nBUG: KMSAN: kernel-infoleak in rseq_set_ids_get_csaddr include/linux/rseq_entry.h:502 [inline]\n\nThe local variable:\n\n\tstruct rseq_ids ids = {\n\t\t.cpu_id\t = task_cpu(t),\n\t\t.mm_cid\t = task_mm_cid(t),\n\t\t.node_id = cpu_to_node(ids.cpu_id),\n\t};\n\nAccording to the C standard, the evaluation order of expressions in an\ninitializer list is indeterminately sequenced. The compiler (Clang, in\nthis KMSAN build) evaluates `cpu_to_node(ids.cpu_id)` *before*\n`ids.cpu_id` is initialized with `task_cpu(t)`.\n\nThis is fixed by moving the assignment of ids.node_id outside the\nstructure initialization."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["include/linux/rseq_entry.h"], "versions": [{"version": "d242126fd21ab8f1631fdbc8589e43a9d4229f3b", "lessThan": "e12d20a63b61aaf9de4772effccf42cc9a003e58", "status": "affected", "versionType": "git"}, {"version": "82f572449cfe75f12ea985986da60e11f308f77d", "lessThan": "6d99479799c69c3cb588fcda19c81d8f61d64ecd", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["include/linux/rseq_entry.h"], "versions": [{"version": "7.0.10", "lessThan": "7.0.13", "status": "affected", "versionType": "semver"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "7.0.10", "versionEndExcluding": "7.0.13"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/e12d20a63b61aaf9de4772effccf42cc9a003e58"}, {"url": "https://git.kernel.org/stable/c/6d99479799c69c3cb588fcda19c81d8f61d64ecd"}], "title": "rseq: Fix using an uninitialized stack variable in rseq_exit_user_update()", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["include/linux/rseq_entry.h"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "e12d20a63b61aaf9de4772effccf42cc9a003e58", "status": "affected", "version": "d242126fd21ab8f1631fdbc8589e43a9d4229f3b", "versionType": "git"}, {"lessThan": "6d99479799c69c3cb588fcda19c81d8f61d64ecd", "status": "affected", "version": "82f572449cfe75f12ea985986da60e11f308f77d", "versionType": "git"}]}, {"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["include/linux/rseq_entry.h"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "7.0.13", "status": "affected", "version": "7.0.10", "versionType": "semver"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "F1B096A9-C4FA-4C91-BDD2-CBF0B2D0C3EE", "versionEndExcluding": "7.0.13", "versionStartIncluding": "7.0.10", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:*", "matchCriteriaId": "EC732D08-5F7B-46D9-B154-E60C7F4F0A97", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:*", "matchCriteriaId": "E5910A9D-F60A-409A-B486-FE66BFEBA9B9", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc5:*:*:*:*:*:*", "matchCriteriaId": "81DFF19E-9CF8-49C6-8C36-1E4038622933", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc6:*:*:*:*:*:*", "matchCriteriaId": "B0E8FC71-3952-444C-83E9-718DBBBEC615", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nrseq: Fix using an uninitialized stack variable in rseq_exit_user_update()\n\nThere is an bug in which an uninitialized stack variable is used in\nrseq_exit_user_update() as reported by syzbot:\n\nBUG: KMSAN: kernel-infoleak in rseq_set_ids_get_csaddr include/linux/rseq_entry.h:502 [inline]\n\nThe local variable:\n\n\tstruct rseq_ids ids = {\n\t\t.cpu_id\t = task_cpu(t),\n\t\t.mm_cid\t = task_mm_cid(t),\n\t\t.node_id = cpu_to_node(ids.cpu_id),\n\t};\n\nAccording to the C standard, the evaluation order of expressions in an\ninitializer list is indeterminately sequenced. The compiler (Clang, in\nthis KMSAN build) evaluates `cpu_to_node(ids.cpu_id)` *before*\n`ids.cpu_id` is initialized with `task_cpu(t)`.\n\nThis is fixed by moving the assignment of ids.node_id outside the\nstructure initialization."}], "id": "CVE-2026-53243", "lastModified": "2026-07-07T22:21:55.840", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 5.5, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 3.6, "source": "nvd@nist.gov", "type": "Primary"}]}, "published": "2026-06-25T09:16:42.260", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/6d99479799c69c3cb588fcda19c81d8f61d64ecd"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/e12d20a63b61aaf9de4772effccf42cc9a003e58"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-908"}], "source": "nvd@nist.gov", "type": "Primary"}]}

{"bugzilla": {"description": "kernel: rseq: Fix using an uninitialized stack variable in rseq_exit_user_update()", "id": "2492767", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2492767"}, "csaw": false, "cwe": "CWE-908", "details": ["A flaw was found in the Linux kernel. An uninitialized stack variable in the `rseq_exit_user_update()` function can lead to an information leak. This occurs due to an indeterminate sequencing of expressions during the initialization of the `rseq_ids` structure, where `ids.node_id` is assigned using an uninitialized `ids.cpu_id`. A local attacker could potentially exploit this to gain sensitive kernel information."], "name": "CVE-2026-53243", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-06-25T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-53243\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-53243\nhttps://lore.kernel.org/linux-cve-announce/2026062511-CVE-2026-53243-0e70@gregkh/T"]}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[d242126fd21ab8f1631fdbc8589e43a9d4229f3b,e12d20a63b61aaf9de4772effccf42cc9a003e58)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[82f572449cfe75f12ea985986da60e11f308f77d,6d99479799c69c3cb588fcda19c81d8f61d64ecd)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[7.0.10,7.0.13)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-06-25T12:00:13.999200+00:00", "updated": "2026-08-12T08:15:04.570553+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}