{"id":"CVE-2026-74500","summary":"ALSA: usb-audio: fix stack info leak in RME Digiface status","details":"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 \u003c 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 \u003cbaul.lee@xbow.com\u003e","modified":"2026-10-28T02:31:03.303516036Z","published":"2026-08-15T12:27:26.359Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74500.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/441aaad150c57edaf57ee482a79a3bf4c5b7e353"},{"type":"WEB","url":"https://git.kernel.org/stable/c/7ba01e0d3539d9cf0aef3e82938f1648147744cc"},{"type":"WEB","url":"https://git.kernel.org/stable/c/98dbfbb38e297c25c5b0af4a9018d71ac25e8554"},{"type":"WEB","url":"https://git.kernel.org/stable/c/b3a346d5c99dd73cf84711f2a43e42691990efd2"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74500.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-74500"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"611a96f6acf2e74fe28cb90908a9c183862348ce"},{"fixed":"b3a346d5c99dd73cf84711f2a43e42691990efd2"},{"fixed":"7ba01e0d3539d9cf0aef3e82938f1648147744cc"},{"fixed":"98dbfbb38e297c25c5b0af4a9018d71ac25e8554"},{"fixed":"441aaad150c57edaf57ee482a79a3bf4c5b7e353"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"6.10.14"},{"fixed":"6.11"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"6.11.3"},{"fixed":"6.12"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"3089703ab71484a8b9a7641051181d11d60f870c"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"50f63f11a6ddaa0d34574df72b3fa6ee257c057d"}]}],"versions":["v6.10.14","v6.11.11","v6.11.10","v6.11.9","v6.11.8","v6.11.7","v6.11.6","v6.11.5","v6.11.4","v6.11.3"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-74500.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.12.0"},{"fixed":"6.12.103"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.44"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.1.8"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-74500.json"}}],"schema_version":"1.9.2"}