{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-93122","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-09-17T16:02:15.086Z","datePublished":"2026-09-17T16:11:27.890Z","dateUpdated":"2026-09-18T17:56:04.397Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-09-18T17:56:04.397Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nusb: gadget: uac: validate rate list length before storing\n\nUAC1 and UAC2 configfs rate-list attributes parse a comma-separated\nlist of sampling rates and store each parsed value in fixed-size arrays.\nThe arrays have UAC_MAX_RATES entries, but the store paths do not check\nthat the input contains at most that many tokens before writing through\nopts->name##s[i++].\n\nWriting more than ten rates therefore writes past the end of the\np_srates[] or c_srates[] array in struct f_uac1_opts or struct\nf_uac2_opts.\n\nWith CONFIG_UBSAN_BOUNDS enabled, writing an 11-entry rate list to the\nUAC1 p_srate attribute reports:\n\n  UBSAN: array-index-out-of-bounds\n  drivers/usb/gadget/function/f_uac1.c:1669:1\n  index 10 is out of range for type 'int [10]'\n  __ubsan_handle_out_of_bounds.cold\n  f_uac1_opts_p_srate_store\n  configfs_write_iter\n  vfs_write\n  ksys_write\n  do_syscall_64\n\nThe same reproducer against the UAC2 p_srate attribute reports:\n\n  UBSAN: array-index-out-of-bounds\n  drivers/usb/gadget/function/f_uac2.c:2087:1\n  index 10 is out of range for type 'int [10]'\n  __ubsan_handle_out_of_bounds.cold\n  f_uac2_opts_p_srate_store\n  configfs_write_iter\n  vfs_write\n  ksys_write\n  do_syscall_64\n\nReject additional tokens once UAC_MAX_RATES entries have been parsed.\nAlso keep the original kstrdup() pointer for kfree(), because strsep()\nadvances the parsing cursor. Freeing the advanced cursor leaks the\noriginal buffer on successful parses and can free an interior pointer on\nsome error paths."}],"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 malformed comma-separated rates enter via write(2)→configfs_write_iter()→f_uac1_opts_p_srate_store/f_uac1_opts_c_srate_store (and the UAC2 twins) on /sys/kernel/config/usb_gadget/<g>/functions/uac{1,2}.*/{p,c}_srate; USB SETUP/iso packets never supply that page.\nAC:L - A fresh function_make() uac1/uac2 instance has opts->refcnt==0, so one write of eleven or more kstrtou32 tokens (up to configfs SIMPLE_ATTR_SIZE-1 bytes) stores through opts->p_srates[i++]/c_srates[i++] past UAC_MAX_RATES with no race or victim state.\nPR:L - f_uac1_opts_p_srate_store and f_uac2_opts_p_srate_store (and the c_srate stores) do no capable() check; CONFIGFS_ATTR is S_IWUSR, and Android/embedded USB gadget HALs routinely chown /sys/kernel/config/usb_gadget to a non-root system or HAL daemon.\nUI:N - The attacker mkdir's the uac1/uac2 function instance and writes the oversized p_srate or c_srate list themselves; no other user must plug a cable, mount a volume, or open a file.\nS:U - The store overwrites the kmalloc'd struct f_uac1_opts/f_uac2_opts and neighbouring host-kernel slab in the same OS authority; it is not a VM escape, IOMMU/DMA bypass, or sandbox breakout.\nC:H - Each extra token is an attacker-chosen u32 written past p_srates[9]/c_srates[9] into the rest of the kzalloc'd opts object and adjacent slab; that heap overflow is groomable into a kernel-memory disclosure primitive.\nI:H - f_uac1_opts_p_srate_store writes attacker-controlled ints past p_srates[] over p_ssize, the 126-byte name arrays, refcnt, and opts->lock, then mutex_unlock()s the corrupted mutex — an arbitrary-write and control-flow hijack primitive.\nA:H - The commit's UBSAN report is array-index-out-of-bounds at f_uac1_opts_p_srate_store/f_uac2_opts_p_srate_store index 10 of int[10]; without UBSAN the same store corrupts opts->lock and adjacent slab and oopses or panics."}]}],"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_uac1.c","drivers/usb/gadget/function/f_uac2.c"],"versions":[{"version":"a7339e4f5788bd088bb0be1f96a6cce459676ed0","lessThan":"3819c6f255a37c4d085ce9f264f9f11bf3c2c6bb","status":"affected","versionType":"git"},{"version":"a7339e4f5788bd088bb0be1f96a6cce459676ed0","lessThan":"844d83d5964b87919b958ff48405188c6ddae9cc","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_uac1.c","drivers/usb/gadget/function/f_uac2.c"],"versions":[{"version":"5.18","status":"affected"},{"version":"0","lessThan":"5.18","status":"unaffected","versionType":"semver"},{"version":"7.2.6","lessThanOrEqual":"7.2.*","status":"unaffected","versionType":"semver"},{"version":"7.3-rc1","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":"5.18","versionEndExcluding":"7.2.6"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.18","versionEndExcluding":"7.3-rc1"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/3819c6f255a37c4d085ce9f264f9f11bf3c2c6bb"},{"url":"https://git.kernel.org/stable/c/844d83d5964b87919b958ff48405188c6ddae9cc"}],"title":"usb: gadget: uac: validate rate list length before storing","x_generator":{"engine":"bippy-1.2.0"}}}}