{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-43274","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-05-01T14:12:55.998Z","datePublished":"2026-05-06T11:28:57.503Z","dateUpdated":"2026-08-05T12:26:59.090Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-08-05T12:26:59.090Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nmailbox: mchp-ipc-sbi: fix out-of-bounds access in mchp_ipc_get_cluster_aggr_irq()\n\nThe cluster_cfg array is dynamically allocated to hold per-CPU\nconfiguration structures, with its size based on the number of online\nCPUs. Previously, this array was indexed using hartid, which may be\nnon-contiguous or exceed the bounds of the array, leading to\nout-of-bounds access.\nSwitch to using cpuid as the index, as it is guaranteed to be within\nthe valid range provided by for_each_online_cpu()."}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","baseScore":8.4,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - The vulnerable code is reached through local platform-driver probe and the local Microchip IPC/IHC interrupt path, not through network packets. A plausible attacker would need local control of the affected platform/IPC peer or firmware configuration to trigger the bad hart/IRQ condition.\nAC:L - The bug is a direct non-contiguous hart ID versus CPU index mismatch with no race or timing requirement. Such hart mappings are plausible for this Microchip RISC-V platform, so triggering does not depend on conditions outside the attacker's control once the affected path is reachable.\nPR:N - The vulnerable probe and IRQ handler perform no Linux credential, capability, or authentication checks. An attacker able to drive the local IPC peer/firmware-triggered path does not need privileges inside the vulnerable Linux instance.\nUI:N - No victim action is required after the affected platform path is reachable. Probe-time setup or an IPC interrupt can hit the vulnerable access automatically.\nS:U - The corruption occurs in the Linux kernel driver and impacts the same kernel security authority. There is no VM escape, IOMMU bypass, or cross-authority boundary shown.\nC:H - The out-of-bounds index can read adjacent kernel memory/pointer fields and feed invalid buffer addresses into the SBI status path. Conservatively, this kernel OOB access can expose sensitive memory.\nI:H - The vulnerable probe path writes `irq`, `buf_base`, and `buf_base_addr` through an out-of-bounds `cluster_cfg[hartid]` index. This is kernel heap memory corruption and can plausibly be leveraged for control-flow or data integrity compromise.\nA:H - The same out-of-bounds access can corrupt kernel memory or dereference/copy through invalid pointers in interrupt context. A kernel oops, panic, or boot-time failure is a high availability impact."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/mailbox/mailbox-mchp-ipc-sbi.c"],"versions":[{"version":"e4b1d67e71419c4af581890ecea84b04920d4116","lessThan":"95438699c92947155823dcd3918049a07f3cd867","status":"affected","versionType":"git"},{"version":"e4b1d67e71419c4af581890ecea84b04920d4116","lessThan":"0442b6229e2eedc95a6d3d18ce75dec7f5b5377c","status":"affected","versionType":"git"},{"version":"e4b1d67e71419c4af581890ecea84b04920d4116","lessThan":"f7c330a8c83c9b0332fd524097eaf3e69148164d","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/mailbox/mailbox-mchp-ipc-sbi.c"],"versions":[{"version":"6.14","status":"affected"},{"version":"0","lessThan":"6.14","status":"unaffected","versionType":"semver"},{"version":"6.18.16","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"6.19.6","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":"6.14","versionEndExcluding":"6.18.16"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.14","versionEndExcluding":"6.19.6"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.14","versionEndExcluding":"7.0"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/95438699c92947155823dcd3918049a07f3cd867"},{"url":"https://git.kernel.org/stable/c/0442b6229e2eedc95a6d3d18ce75dec7f5b5377c"},{"url":"https://git.kernel.org/stable/c/f7c330a8c83c9b0332fd524097eaf3e69148164d"}],"title":"mailbox: mchp-ipc-sbi: fix out-of-bounds access in mchp_ipc_get_cluster_aggr_irq()","x_generator":{"engine":"bippy-1.2.0"}}}}