{"id":"CVE-2026-99216","state":"PUBLISHED","title":"Drivers: hv: Don't reset VMBus connection state on error/exit paths","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nDrivers: hv: Don't reset VMBus connection state on error/exit paths\n\nIn two places, current code forces vmbus_connection.conn_state to\nDISCONNECTED prior to calling vmbus_disconnect(). But vmbus_disconnect()\ncalls vmbus_initiate_unload(), which unloads the VMBus connection\nonly if the conn_state is CONNECTED. Consequently, the connection\nremains and the Hyper-V host might continue to send messages or post\nVMBus interrupts.\n\nThe problem was introduced in commit 74347a99e73ae (\"x86/Hyper-V:\nUnload vmbus channel in hv panic callback\"), in that\nvmbus_initiate_unload() started checking the current connection\nstate before doing the unload. This commit removed some occurrences\nwhere conn_state was forced to DISCONNECTED, but these two remained,\napparently due to an oversight at the time.\n\nFix this by not forcing conn_state to DISCONNECTED during VMBus exit,\nor if a failure occurs when establishing the connection in the first\nplace. Whatever value conn_state has at the time is then read by\nvmbus_initiate_unload() to determine if there is a connection to\nbe unloaded.","publishedAt":"2026-10-28T10:36:09.383Z","updatedAt":"2026-10-30T12:43:02.003Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"74347a99e73ae00b8385f1209aaea193c670f901","status":"affected","lessThan":"2939215d57bc8e4189290544fca78f3809ac3ef8","versionType":"git"},{"version":"74347a99e73ae00b8385f1209aaea193c670f901","status":"affected","lessThan":"a0ae955ba9a5067a157ebb8defb4a0a9cb1fc304","versionType":"git"},{"version":"74347a99e73ae00b8385f1209aaea193c670f901","status":"affected","lessThan":"deef3ab5129ae4c45662c957cdab3739eb047fb1","versionType":"git"},{"version":"74347a99e73ae00b8385f1209aaea193c670f901","status":"affected","lessThan":"2e5ffbf1e41abbf6e02ce28115107938f55ff646","versionType":"git"},{"version":"74347a99e73ae00b8385f1209aaea193c670f901","status":"affected","lessThan":"2732210132f92aca0622b5134027990a809279d5","versionType":"git"},{"version":"74347a99e73ae00b8385f1209aaea193c670f901","status":"affected","lessThan":"f47ce27af80b87cc684d5c12b65506af498ac7e5","versionType":"git"},{"version":"74347a99e73ae00b8385f1209aaea193c670f901","status":"affected","lessThan":"3195546a377c2d8d176d837e8baad5ce15d11195","versionType":"git"},{"version":"74347a99e73ae00b8385f1209aaea193c670f901","status":"affected","lessThan":"ec31dc39e835ccde0930daccece8c492d28282fc","versionType":"git"},{"version":"5e059fc0f054309036d3f612bc8b0a502ca58545","status":"affected","versionType":"git"},{"version":"9f38f7b46de0747c1909e8c557aa21715dce20c5","status":"affected","versionType":"git"},{"version":"caeeb3787167c884b955404a7e669fd77f267e44","status":"affected","versionType":"git"},{"version":"4.19.118","status":"affected","lessThan":"4.20","versionType":"semver"},{"version":"5.4.35","status":"affected","lessThan":"5.5","versionType":"semver"},{"version":"5.6.7","status":"affected","lessThan":"5.7","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/hv/connection.c","drivers/hv/vmbus_drv.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.7","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.7","versionType":"semver"},{"version":"5.10.273","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.224","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.191","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.161","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.115","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.59","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.13","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/hv/connection.c","drivers/hv/vmbus_drv.c"]}],"references":["https://git.kernel.org/stable/c/2939215d57bc8e4189290544fca78f3809ac3ef8","https://git.kernel.org/stable/c/a0ae955ba9a5067a157ebb8defb4a0a9cb1fc304","https://git.kernel.org/stable/c/deef3ab5129ae4c45662c957cdab3739eb047fb1","https://git.kernel.org/stable/c/2e5ffbf1e41abbf6e02ce28115107938f55ff646","https://git.kernel.org/stable/c/2732210132f92aca0622b5134027990a809279d5","https://git.kernel.org/stable/c/f47ce27af80b87cc684d5c12b65506af498ac7e5","https://git.kernel.org/stable/c/3195546a377c2d8d176d837e8baad5ce15d11195","https://git.kernel.org/stable/c/ec31dc39e835ccde0930daccece8c492d28282fc"],"weaknesses":[],"ingestedAt":"2026-10-30T13:02:04.640Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/99xxx/CVE-2026-99216.json","commit":"cb14bf1b43b0c9f05f7f40eae2246263fd430780","baselineCommit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-99216","state":"PUBLISHED","datePublished":"2026-10-28T10:36:09.383Z","dateUpdated":"2026-10-30T12:43:02.003Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-25T10:25:14.401Z"},"containers":{"cna":{"title":"Drivers: hv: Don't reset VMBus connection state on error/exit paths","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nDrivers: hv: Don't reset VMBus connection state on error/exit paths\n\nIn two places, current code forces vmbus_connection.conn_state to\nDISCONNECTED prior to calling vmbus_disconnect(). But vmbus_disconnect()\ncalls vmbus_initiate_unload(), which unloads the VMBus connection\nonly if the conn_state is CONNECTED. Consequently, the connection\nremains and the Hyper-V host might continue to send messages or post\nVMBus interrupts.\n\nThe problem was introduced in commit 74347a99e73ae (\"x86/Hyper-V:\nUnload vmbus channel in hv panic callback\"), in that\nvmbus_initiate_unload() started checking the current connection\nstate before doing the unload. This commit removed some occurrences\nwhere conn_state was forced to DISCONNECTED, but these two remained,\napparently due to an oversight at the time.\n\nFix this by not forcing conn_state to DISCONNECTED during VMBus exit,\nor if a failure occurs when establishing the connection in the first\nplace. Whatever value conn_state has at the time is then read by\nvmbus_initiate_unload() to determine if there is a connection to\nbe unloaded."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"74347a99e73ae00b8385f1209aaea193c670f901","status":"affected","lessThan":"2939215d57bc8e4189290544fca78f3809ac3ef8","versionType":"git"},{"version":"74347a99e73ae00b8385f1209aaea193c670f901","status":"affected","lessThan":"a0ae955ba9a5067a157ebb8defb4a0a9cb1fc304","versionType":"git"},{"version":"74347a99e73ae00b8385f1209aaea193c670f901","status":"affected","lessThan":"deef3ab5129ae4c45662c957cdab3739eb047fb1","versionType":"git"},{"version":"74347a99e73ae00b8385f1209aaea193c670f901","status":"affected","lessThan":"2e5ffbf1e41abbf6e02ce28115107938f55ff646","versionType":"git"},{"version":"74347a99e73ae00b8385f1209aaea193c670f901","status":"affected","lessThan":"2732210132f92aca0622b5134027990a809279d5","versionType":"git"},{"version":"74347a99e73ae00b8385f1209aaea193c670f901","status":"affected","lessThan":"f47ce27af80b87cc684d5c12b65506af498ac7e5","versionType":"git"},{"version":"74347a99e73ae00b8385f1209aaea193c670f901","status":"affected","lessThan":"3195546a377c2d8d176d837e8baad5ce15d11195","versionType":"git"},{"version":"74347a99e73ae00b8385f1209aaea193c670f901","status":"affected","lessThan":"ec31dc39e835ccde0930daccece8c492d28282fc","versionType":"git"},{"version":"5e059fc0f054309036d3f612bc8b0a502ca58545","status":"affected","versionType":"git"},{"version":"9f38f7b46de0747c1909e8c557aa21715dce20c5","status":"affected","versionType":"git"},{"version":"caeeb3787167c884b955404a7e669fd77f267e44","status":"affected","versionType":"git"},{"version":"4.19.118","status":"affected","lessThan":"4.20","versionType":"semver"},{"version":"5.4.35","status":"affected","lessThan":"5.5","versionType":"semver"},{"version":"5.6.7","status":"affected","lessThan":"5.7","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/hv/connection.c","drivers/hv/vmbus_drv.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.7","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.7","versionType":"semver"},{"version":"5.10.273","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.224","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.191","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.161","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.115","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.59","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.13","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/hv/connection.c","drivers/hv/vmbus_drv.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/2939215d57bc8e4189290544fca78f3809ac3ef8"},{"url":"https://git.kernel.org/stable/c/a0ae955ba9a5067a157ebb8defb4a0a9cb1fc304"},{"url":"https://git.kernel.org/stable/c/deef3ab5129ae4c45662c957cdab3739eb047fb1"},{"url":"https://git.kernel.org/stable/c/2e5ffbf1e41abbf6e02ce28115107938f55ff646"},{"url":"https://git.kernel.org/stable/c/2732210132f92aca0622b5134027990a809279d5"},{"url":"https://git.kernel.org/stable/c/f47ce27af80b87cc684d5c12b65506af498ac7e5"},{"url":"https://git.kernel.org/stable/c/3195546a377c2d8d176d837e8baad5ce15d11195"},{"url":"https://git.kernel.org/stable/c/ec31dc39e835ccde0930daccece8c492d28282fc"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-30T12:43:02.003Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.7","versionEndExcluding":"5.10.273"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.7","versionEndExcluding":"5.15.224"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.7","versionEndExcluding":"6.1.191"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.7","versionEndExcluding":"6.6.161"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.7","versionEndExcluding":"6.12.115"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.7","versionEndExcluding":"6.18.59"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.7","versionEndExcluding":"7.2.13"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*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