{"id":"CVE-2026-93096","state":"PUBLISHED","title":"cxl/features: Serialize multi-part Get/Set Feature transfers","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ncxl/features: Serialize multi-part Get/Set Feature transfers\n\nA Get or Set Feature payload larger than the mailbox payload size is\nsplit into several mailbox commands. mbox_mutex only serializes\nindividual mailbox commands and is dropped between iterations of these\nloops. Nothing serializes the multi-part transfer as a whole.\ncxl_get_feature() and cxl_set_feature() are reachable concurrently\nfrom fwctl (per-fd RPCs run under a read-held registration lock) and\nfrom the EDAC scrub/ECS/repair paths, so two transfers to the same\nmailbox can interleave their parts and corrupt the device's transfer\ncontext.\n\nAdd a per-mailbox feat_mutex and hold it across the whole transfer in\nboth functions. It nests outside mbox_mutex (which is taken inside\ncxl_internal_send_cmd()), and is taken nowhere else, so no lock-ordering\ninversion is introduced.","publishedAt":"2026-09-17T16:11:10.359Z","updatedAt":"2026-10-19T09:05:29.455Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"5e5ac21f629de796ab5d598b59c5e468c6fe4f95","status":"affected","lessThan":"c6492e17412048387435f256ffafc4dd6518db28","versionType":"git"},{"version":"5e5ac21f629de796ab5d598b59c5e468c6fe4f95","status":"affected","lessThan":"7682b617db1f19bc606b5f1badadcf1e63a87b14","versionType":"git"},{"version":"5e5ac21f629de796ab5d598b59c5e468c6fe4f95","status":"affected","lessThan":"77b814c1832fde018c30357b4ec3fcdaa91a1c10","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/cxl/core/features.c","drivers/cxl/core/mbox.c","include/cxl/mailbox.h"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.15","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.15","versionType":"semver"},{"version":"6.18.57","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.6","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/cxl/core/features.c","drivers/cxl/core/mbox.c","include/cxl/mailbox.h"]}],"references":["https://git.kernel.org/stable/c/c6492e17412048387435f256ffafc4dd6518db28","https://git.kernel.org/stable/c/7682b617db1f19bc606b5f1badadcf1e63a87b14","https://git.kernel.org/stable/c/77b814c1832fde018c30357b4ec3fcdaa91a1c10"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:34.582Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/93xxx/CVE-2026-93096.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-93096","state":"PUBLISHED","datePublished":"2026-09-17T16:11:10.359Z","dateUpdated":"2026-10-19T09:05:29.455Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-17T16:02:15.084Z"},"containers":{"cna":{"title":"cxl/features: Serialize multi-part Get/Set Feature transfers","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ncxl/features: Serialize multi-part Get/Set Feature transfers\n\nA Get or Set Feature payload larger than the mailbox payload size is\nsplit into several mailbox commands. mbox_mutex only serializes\nindividual mailbox commands and is dropped between iterations of these\nloops. Nothing serializes the multi-part transfer as a whole.\ncxl_get_feature() and cxl_set_feature() are reachable concurrently\nfrom fwctl (per-fd RPCs run under a read-held registration lock) and\nfrom the EDAC scrub/ECS/repair paths, so two transfers to the same\nmailbox can interleave their parts and corrupt the device's transfer\ncontext.\n\nAdd a per-mailbox feat_mutex and hold it across the whole transfer in\nboth functions. It nests outside mbox_mutex (which is taken inside\ncxl_internal_send_cmd()), and is taken nowhere else, so no lock-ordering\ninversion is introduced."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"5e5ac21f629de796ab5d598b59c5e468c6fe4f95","status":"affected","lessThan":"c6492e17412048387435f256ffafc4dd6518db28","versionType":"git"},{"version":"5e5ac21f629de796ab5d598b59c5e468c6fe4f95","status":"affected","lessThan":"7682b617db1f19bc606b5f1badadcf1e63a87b14","versionType":"git"},{"version":"5e5ac21f629de796ab5d598b59c5e468c6fe4f95","status":"affected","lessThan":"77b814c1832fde018c30357b4ec3fcdaa91a1c10","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/cxl/core/features.c","drivers/cxl/core/mbox.c","include/cxl/mailbox.h"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.15","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.15","versionType":"semver"},{"version":"6.18.57","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.6","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/cxl/core/features.c","drivers/cxl/core/mbox.c","include/cxl/mailbox.h"]}],"references":[{"url":"https://git.kernel.org/stable/c/c6492e17412048387435f256ffafc4dd6518db28"},{"url":"https://git.kernel.org/stable/c/7682b617db1f19bc606b5f1badadcf1e63a87b14"},{"url":"https://git.kernel.org/stable/c/77b814c1832fde018c30357b4ec3fcdaa91a1c10"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-19T09:05:29.455Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.15","versionEndExcluding":"6.18.57"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.15","versionEndExcluding":"7.2.6"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.15","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}