{"id":"CVE-2026-74500","state":"PUBLISHED","title":"ALSA: usb-audio: fix stack info leak in RME Digiface status","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nALSA: usb-audio: fix stack info leak in RME Digiface status\n\nsnd_rme_digiface_read_status() reads a four-word status block from the\ndevice into an uninitialised on-stack __le32 buf[4] and, whenever the\nvendor control-IN transfer does not return a negative error, copies all\nfour words into the caller's status[].\n\nsnd_usb_ctl_msg() copies the full requested size back into the caller's\nbuffer regardless of how many bytes the data stage actually delivered:\n\n\tbuf = kmemdup(data, size, GFP_KERNEL);\n\terr = usb_control_msg(dev, pipe, request, requesttype,\n\t\t\t      value, index, buf, size, timeout);\n\tmemcpy(data, buf, size);\n\nusb_control_msg() returns the transferred length on a short control-IN,\nwhich is a non-negative value, and writes only that many bytes.  The\nremainder of the copy back is the kmemdup()ed image of the caller's\nbuffer, so a device answering with a short data stage leaves the\ntrailing words of buf[] holding leftover kernel stack.  The only guard\nin the caller is err < 0, so those words are stored into status[].\n\nThey then reach user space: snd_rme_digiface_get_status_val() selects a\n16-bit halfword of status[] per the control's reg/mask, and the eight\nDigiface status controls together expose the whole 16-byte frame to an\nunprivileged reader of /dev/snd/controlC*.\n\nZero-initialise the buffer so a short read yields zeros instead of stack\nresidue.  This mirrors snd_rme_get_status1(), which already clears its\noutput word before the same kind of vendor read.\n\nDiscovered by XBOW, triaged by Baul Lee <baul.lee@xbow.com>","publishedAt":"2026-08-15T12:27:26.359Z","updatedAt":"2026-08-17T05:20:38.636Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"611a96f6acf2e74fe28cb90908a9c183862348ce","status":"affected","lessThan":"b3a346d5c99dd73cf84711f2a43e42691990efd2","versionType":"git"},{"version":"611a96f6acf2e74fe28cb90908a9c183862348ce","status":"affected","lessThan":"7ba01e0d3539d9cf0aef3e82938f1648147744cc","versionType":"git"},{"version":"611a96f6acf2e74fe28cb90908a9c183862348ce","status":"affected","lessThan":"98dbfbb38e297c25c5b0af4a9018d71ac25e8554","versionType":"git"},{"version":"611a96f6acf2e74fe28cb90908a9c183862348ce","status":"affected","lessThan":"441aaad150c57edaf57ee482a79a3bf4c5b7e353","versionType":"git"},{"version":"3089703ab71484a8b9a7641051181d11d60f870c","status":"affected","versionType":"git"},{"version":"50f63f11a6ddaa0d34574df72b3fa6ee257c057d","status":"affected","versionType":"git"},{"version":"6.10.14","status":"affected","lessThan":"6.11","versionType":"semver"},{"version":"6.11.3","status":"affected","lessThan":"6.12","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["sound/usb/mixer_quirks.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.12","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.12","versionType":"semver"},{"version":"6.12.103","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.44","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.8","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["sound/usb/mixer_quirks.c"]}],"references":["https://git.kernel.org/stable/c/b3a346d5c99dd73cf84711f2a43e42691990efd2","https://git.kernel.org/stable/c/7ba01e0d3539d9cf0aef3e82938f1648147744cc","https://git.kernel.org/stable/c/98dbfbb38e297c25c5b0af4a9018d71ac25e8554","https://git.kernel.org/stable/c/441aaad150c57edaf57ee482a79a3bf4c5b7e353"],"weaknesses":[],"ingestedAt":"2026-10-29T20:12:58.252Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/74xxx/CVE-2026-74500.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-74500","state":"PUBLISHED","datePublished":"2026-08-15T12:27:26.359Z","dateUpdated":"2026-08-17T05:20:38.636Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-08-15T05:44:03.907Z"},"containers":{"cna":{"title":"ALSA: usb-audio: fix stack info leak in RME Digiface status","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nALSA: usb-audio: fix stack info leak in RME Digiface status\n\nsnd_rme_digiface_read_status() reads a four-word status block from the\ndevice into an uninitialised on-stack __le32 buf[4] and, whenever the\nvendor control-IN transfer does not return a negative error, copies all\nfour words into the caller's status[].\n\nsnd_usb_ctl_msg() copies the full requested size back into the caller's\nbuffer regardless of how many bytes the data stage actually delivered:\n\n\tbuf = kmemdup(data, size, GFP_KERNEL);\n\terr = usb_control_msg(dev, pipe, request, requesttype,\n\t\t\t      value, index, buf, size, timeout);\n\tmemcpy(data, buf, size);\n\nusb_control_msg() returns the transferred length on a short control-IN,\nwhich is a non-negative value, and writes only that many bytes.  The\nremainder of the copy back is the kmemdup()ed image of the caller's\nbuffer, so a device answering with a short data stage leaves the\ntrailing words of buf[] holding leftover kernel stack.  The only guard\nin the caller is err < 0, so those words are stored into status[].\n\nThey then reach user space: snd_rme_digiface_get_status_val() selects a\n16-bit halfword of status[] per the control's reg/mask, and the eight\nDigiface status controls together expose the whole 16-byte frame to an\nunprivileged reader of /dev/snd/controlC*.\n\nZero-initialise the buffer so a short read yields zeros instead of stack\nresidue.  This mirrors snd_rme_get_status1(), which already clears its\noutput word before the same kind of vendor read.\n\nDiscovered by XBOW, triaged by Baul Lee <baul.lee@xbow.com>"}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"611a96f6acf2e74fe28cb90908a9c183862348ce","status":"affected","lessThan":"b3a346d5c99dd73cf84711f2a43e42691990efd2","versionType":"git"},{"version":"611a96f6acf2e74fe28cb90908a9c183862348ce","status":"affected","lessThan":"7ba01e0d3539d9cf0aef3e82938f1648147744cc","versionType":"git"},{"version":"611a96f6acf2e74fe28cb90908a9c183862348ce","status":"affected","lessThan":"98dbfbb38e297c25c5b0af4a9018d71ac25e8554","versionType":"git"},{"version":"611a96f6acf2e74fe28cb90908a9c183862348ce","status":"affected","lessThan":"441aaad150c57edaf57ee482a79a3bf4c5b7e353","versionType":"git"},{"version":"3089703ab71484a8b9a7641051181d11d60f870c","status":"affected","versionType":"git"},{"version":"50f63f11a6ddaa0d34574df72b3fa6ee257c057d","status":"affected","versionType":"git"},{"version":"6.10.14","status":"affected","lessThan":"6.11","versionType":"semver"},{"version":"6.11.3","status":"affected","lessThan":"6.12","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["sound/usb/mixer_quirks.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.12","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.12","versionType":"semver"},{"version":"6.12.103","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.44","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.8","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["sound/usb/mixer_quirks.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/b3a346d5c99dd73cf84711f2a43e42691990efd2"},{"url":"https://git.kernel.org/stable/c/7ba01e0d3539d9cf0aef3e82938f1648147744cc"},{"url":"https://git.kernel.org/stable/c/98dbfbb38e297c25c5b0af4a9018d71ac25e8554"},{"url":"https://git.kernel.org/stable/c/441aaad150c57edaf57ee482a79a3bf4c5b7e353"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-17T05:20:38.636Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.12","versionEndExcluding":"6.12.103"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.12","versionEndExcluding":"6.18.44"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.12","versionEndExcluding":"7.1.8"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.12","versionEndExcluding":"7.2"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.10.14"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.11.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}