CVE-2026-31553

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-31553", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-03-09T15:48:24.115Z", "datePublished": "2026-04-24T14:35:37.828Z", "dateUpdated": "2026-08-05T12:23:27.579Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:23:27.579Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: arm64: Fix the descriptor address in __kvm_at_swap_desc()\n\nUsing \"(u64 __user *)hva + offset\" to get the virtual addresses of S1/S2\ndescriptors looks really wrong, if offset is not zero. What we want to get\nfor swapping is hva + offset, not hva + offset*8. ;-)\n\nFix it."}], "metrics": [{"cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H", "baseScore": 8.8, "baseSeverity": "HIGH"}, "scenarios": [{"lang": "en", "value": "AV:L - The vulnerable path is reached by local execution of a KVM vCPU that traps arm64 AT instructions through KVM_RUN. It is not reachable by network packets or physical input.\nAC:L - The attacker can control the guest/nested page-table layout, enable hardware Access Flag management, choose a nonzero descriptor offset, and execute the trapping AT instruction. No race or external condition is required.\nPR:L - Exploitation requires control of guest or VM execution state, such as a tenant/guest operator able to run a nested-virtualization-capable VM, but not host administrator privileges. Given uncertainty, this is scored as low rather than high privilege.\nUI:N - No victim action is required once the attacker can run the malicious guest code. The trigger is a direct guest instruction/emulation path.\nS:C - This is a KVM guest-triggered bug in host-side emulation, so a plausible exploit crosses the VM isolation boundary. Corruption can affect memory in the host VMM/VM backing context rather than only the guest instruction stream.\nC:H - The incorrect pointer arithmetic creates guest-controlled memory corruption in the host userspace address used for VM memory, which can be leveraged as part of a VM escape. Per the overestimation rule, this is treated as high confidentiality impact.\nI:H - The CAS targets the wrong address and can write an attacker-influenced descriptor value outside the intended page-table entry. This is a memory corruption primitive with plausible control-flow or data integrity consequences in the VMM/VM boundary context.\nA:H - Repeated triggering can corrupt translation descriptors or adjacent VM/VMM memory and can reliably break guest execution or the VMM handling path. Kernel/KVM memory-corruption paths are scored as high availability impact."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["arch/arm64/kvm/at.c"], "versions": [{"version": "f6927b41d57390c597a126063e2e518911976878", "lessThan": "4307e05e568782fc92eff651b09ee5dee88a058d", "status": "affected", "versionType": "git"}, {"version": "f6927b41d57390c597a126063e2e518911976878", "lessThan": "0496acc42fb51eee040b5170cec05cec41385540", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["arch/arm64/kvm/at.c"], "versions": [{"version": "6.19", "status": "affected"}, {"version": "0", "lessThan": "6.19", "status": "unaffected", "versionType": "semver"}, {"version": "6.19.11", "lessThanOrEqual": "6.19.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.0", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.19", "versionEndExcluding": "6.19.11"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.19", "versionEndExcluding": "7.0"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/4307e05e568782fc92eff651b09ee5dee88a058d"}, {"url": "https://git.kernel.org/stable/c/0496acc42fb51eee040b5170cec05cec41385540"}], "title": "KVM: arm64: Fix the descriptor address in __kvm_at_swap_desc()", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["arch/arm64/kvm/at.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "4307e05e568782fc92eff651b09ee5dee88a058d", "status": "affected", "version": "f6927b41d57390c597a126063e2e518911976878", "versionType": "git"}, {"lessThan": "0496acc42fb51eee040b5170cec05cec41385540", "status": "affected", "version": "f6927b41d57390c597a126063e2e518911976878", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["arch/arm64/kvm/at.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "6.19"}, {"lessThan": "6.19", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.19.*", "status": "unaffected", "version": "6.19.11", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.0", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "5054C854-C253-4020-BD2E-2BDA121E424C", "versionEndExcluding": "6.19.11", "versionStartIncluding": "6.19.1", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.19:-:*:*:*:*:*:*", "matchCriteriaId": "35C8A871-4971-433E-A046-FC9F7B7D190A", "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", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:*", "matchCriteriaId": "02259FDA-961B-47BC-AE7F-93D7EC6E90C2", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:*", "matchCriteriaId": "58A9FEFF-C040-420D-8F0A-BFDAAA1DF258", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:*", "matchCriteriaId": "1D2315C0-D46F-4F85-9754-F9E5E11374A6", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc7:*:*:*:*:*:*", "matchCriteriaId": "512EE3A8-A590-4501-9A94-5D4B268D6138", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: arm64: Fix the descriptor address in __kvm_at_swap_desc()\n\nUsing \"(u64 __user *)hva + offset\" to get the virtual addresses of S1/S2\ndescriptors looks really wrong, if offset is not zero. What we want to get\nfor swapping is hva + offset, not hva + offset*8. ;-)\n\nFix it."}, {"lang": "es", "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nKVM: arm64: Corrige la direcci\u00f3n del descriptor en __kvm_at_swap_desc()\n\nUsar \u2019(u64 __user *)hva + offset\u2019 para obtener las direcciones virtuales de los descriptores S1/S2 parece realmente incorrecto, si offset no es cero. Lo que queremos obtener para el intercambio es hva + offset, no hva + offset8. ;-)\n\nCorregido."}], "id": "CVE-2026-31553", "lastModified": "2026-11-11T23:10:00.263", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 8.8, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "CHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 2.0, "impactScore": 6.0, "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary"}]}, "published": "2026-04-24T15:16:29.633", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/0496acc42fb51eee040b5170cec05cec41385540"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/4307e05e568782fc92eff651b09ee5dee88a058d"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "NVD-CWE-noinfo"}], "source": "nvd@nist.gov", "type": "Primary"}]}

{"bugzilla": {"description": "kernel: KVM: arm64: Fix the descriptor address in __kvm_at_swap_desc()", "id": "2461560", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2461560"}, "csaw": false, "cwe": "CWE-468", "details": ["A flaw was found in the Linux kernel's KVM (Kernel-based Virtual Machine) component. Specifically, in the ARM64 architecture, an incorrect calculation of the descriptor address in the `__kvm_at_swap_desc()` function could lead to memory corruption. This vulnerability may allow an attacker to cause system instability or affect the integrity of virtual machines."], "name": "CVE-2026-31553", "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": "2026-04-24T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-31553\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-31553\nhttps://lore.kernel.org/linux-cve-announce/2026042456-CVE-2026-31553-0d39@gregkh/T"]}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[f6927b41d57390c597a126063e2e518911976878,4307e05e568782fc92eff651b09ee5dee88a058d)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[f6927b41d57390c597a126063e2e518911976878,0496acc42fb51eee040b5170cec05cec41385540)"}}], "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": "generic", "value": "6.19"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,6.19)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.19.11,6.20.0]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,*]"}}], "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"}], "analysis": {"en": {"generated_at": "2026-04-28T14:16:41.233969+00:00", "value": {"mitigation_remediation": ["Upgrade the kernel to a patched version that includes the __kvm_at_swap_desc() fix, such as Linux\u00a06.19.1 or any 7.x release beyond rc7.", "If upgrading cannot be performed immediately, disable KVM on affected hosts or restrict guest privileges to prevent access to legacy descriptor swaps.", "Alternatively, apply the specific kernel patch from commit 0496acc42fb51eee040b5170cec05cec41385540, rebuild, and deploy the updated kernel to the affected systems."], "summary": {"action": "Patch Kernel", "impact": "Privilege escalation via KVM memory corruption"}, "threat_synthesis": {"affected_systems": "The flaw affects the Linux kernel on arm64 for all builds 6.19 and the 7.0 release candidates (rc1 through rc7). It is relevant for any Linux distribution that ships these kernel versions and has KVM enabled.", "description_and_impact": "KVM for arm64 contains a bug in the __kvm_at_swap_desc() routine where a descriptor address is calculated incorrectly. The code uses (u64 __user *)hva + offset instead of hva + offset, which can cause memory corruption when offset is non\u2011zero. This flaw could enable an attacker to corrupt kernel memory or execute arbitrary code within the KVM environment, leading to privilege escalation on the host.", "risk_and_exploitability": "The CVSS score of 8.8 indicates high severity, while the EPSS score of less than 1% suggests a low current likelihood of exploitation. The vulnerability is not listed in CISA's KEV catalog, implying no known active exploits. Inference: the flaw is in the KVM core and could be triggered by a guest with sufficient privileges or by a local attacker able to manipulate virtual memory offsets. As a result, the risk remains significant for environments running KVM on the affected kernel releases."}}}}, "created": "2026-04-27T19:15:11.617610+00:00", "updated": "2026-04-28T14:30:33.739755+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}