{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-90022","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-09-11T19:38:34.781Z","datePublished":"2026-09-16T10:33:26.238Z","dateUpdated":"2026-09-17T09:29:26.435Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-09-17T09:29:26.435Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nusb: gadget: f_midi2: fix use-after-free in string attribute show path\n\nf_midi2_opts_str_show() takes the string lock internally, but its\ncallers dereference the opts->info.<field> pointer before calling it,\noutside the lock. This races with f_midi2_opts_str_store(), which\nfrees the old string under opts->lock when the attribute is written\nconcurrently, the show path can read a pointer that gets freed\nbefore the lock inside str_show() is even taken.\n\nChange f_midi2_opts_str_show() to take a pointer to the string field,\nmatching the existing pattern in f_midi2_opts_str_store(), and\ndereference it only after the lock is held. Update all three callers\n(iface_name, block name, and the EP string option macro) accordingly."}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - The UAF is reached by concurrent local read/write of midi2 configfs string attributes (iface_name, ep_name, product_id, block name) under /sys/kernel/config/usb_gadget/<g>/functions/midi2.*; no USB host packets, cable, or UDC bind are required, matching other gadget configfs bugs scored Local rather than Physical.\nAC:L - The attacker controls both sides by opening the same attribute on two fds (configfs serializes only per-fd) and racing show against store; store kfree()s the prior kstrndup string under opts->lock while show already holds the stale pointer, and the function need not be bound (store fails only if refcnt != 0).\nPR:L - gadgets_make(), function_make(), and the midi2 show/store handlers perform no capable() check; access is gated only by configfs DAC, and Android/embedded USB gadget HALs routinely chown /sys/kernel/config/usb_gadget to non-root system or daemon accounts.\nUI:N - The attacker creates the midi2 function instance and performs the concurrent attribute read/write themselves; configfs is typically already mounted at /sys/kernel/config, and no victim mount, cable plug, or other-user action is required.\nS:U - The use-after-free of the configfs kstrndup string corrupts kernel heap within the same host kernel security authority; this is not a VM escape, sandbox breakout, or IOMMU/DMA boundary bypass.\nC:H - Callers load opts->info.<field> outside the lock, then f_midi2_opts_str_show() scnprintfs that pointer after a concurrent store kfree()d it; reclaiming the kmalloc object lets the attacker control the bytes copied to userspace, a UAF disclosure primitive.\nI:H - The same UAF of the kstrndup string, with store spraying attacker-chosen size and content into the same slab, is a classic heap use-after-free that can be converted into overlapping objects, arbitrary write, and control-flow hijack.\nA:H - scnprintf() of the freed string after kfree() reliably produces a KASAN slab-use-after-free oops or kernel panic, which the attacker can retrigger with further concurrent show/store loops."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/usb/gadget/function/f_midi2.c"],"versions":[{"version":"29ee7a4dddd5caa18d1cef000f20c6af43f762f1","lessThan":"f9bdf4c4f6410a1dfafafa383a0e21069372657f","status":"affected","versionType":"git"},{"version":"29ee7a4dddd5caa18d1cef000f20c6af43f762f1","lessThan":"d11f3300b39e2daad2f0d9d66ddcc39a156cb594","status":"affected","versionType":"git"},{"version":"29ee7a4dddd5caa18d1cef000f20c6af43f762f1","lessThan":"e89e30f0b5d3004fe5955250bd8b04f3733e32ce","status":"affected","versionType":"git"},{"version":"29ee7a4dddd5caa18d1cef000f20c6af43f762f1","lessThan":"49fab5e1bdb205c36c965d0e9677bc40d282d3a2","status":"affected","versionType":"git"},{"version":"29ee7a4dddd5caa18d1cef000f20c6af43f762f1","lessThan":"fed0aa7c6eaedc6c0d4e362fc91724aa47be4a7b","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/usb/gadget/function/f_midi2.c"],"versions":[{"version":"6.6","status":"affected"},{"version":"0","lessThan":"6.6","status":"unaffected","versionType":"semver"},{"version":"6.6.157","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.110","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.51","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.2.5","lessThanOrEqual":"7.2.*","status":"unaffected","versionType":"semver"},{"version":"7.3-rc2","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":"6.6","versionEndExcluding":"6.6.157"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.6","versionEndExcluding":"6.12.110"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.6","versionEndExcluding":"6.18.51"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.6","versionEndExcluding":"7.2.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.6","versionEndExcluding":"7.3-rc2"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/f9bdf4c4f6410a1dfafafa383a0e21069372657f"},{"url":"https://git.kernel.org/stable/c/d11f3300b39e2daad2f0d9d66ddcc39a156cb594"},{"url":"https://git.kernel.org/stable/c/e89e30f0b5d3004fe5955250bd8b04f3733e32ce"},{"url":"https://git.kernel.org/stable/c/49fab5e1bdb205c36c965d0e9677bc40d282d3a2"},{"url":"https://git.kernel.org/stable/c/fed0aa7c6eaedc6c0d4e362fc91724aa47be4a7b"}],"title":"usb: gadget: f_midi2: fix use-after-free in string attribute show path","x_generator":{"engine":"bippy-1.2.0"}}}}