{"id":"CVE-2026-97931","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nALSA: us122l: Prevent write upgrades for read mappings\n\nThe hwdep mmap callback rejects read-buffer mappings that are initially\nwritable, but leaves VM_MAYWRITE set on …","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nALSA: us122l: Prevent write upgrades for read mappings\n\nThe hwdep mmap callback rejects read-buffer mappings that are initially\nwritable, but leaves VM_MAYWRITE set on …","severity":"high","cvss":7,"cvssVector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-787"],"vendor":"Linux","product":"Linux","affected":["Linux >= 030a07e441296c372f946cd4065b5d831d8dc40c < cbc1f954ce67d739d41d1f0757d29850353ebb6a","Linux >= 030a07e441296c372f946cd4065b5d831d8dc40c < becb89036a1320ef0a77da2d27935ac0704345c4","Linux >= 030a07e441296c372f946cd4065b5d831d8dc40c < 6a5f5a5a32c78e67701f1d0f26bc87af68895604","Linux >= 030a07e441296c372f946cd4065b5d831d8dc40c < 938e8d6cee8d36f24669dfdcd3717e081eb32d64","Linux >= 030a07e441296c372f946cd4065b5d831d8dc40c < 64a87950239867682cde128020e1a47088295e5c","Linux >= 030a07e441296c372f946cd4065b5d831d8dc40c < d9c537b14f4982f17b103e3a2cfeee4bee6bc026","Linux >= 030a07e441296c372f946cd4065b5d831d8dc40c < 0eb9dd4774af0ac4d1fd105ef2b0a1f6cec06f2f","Linux >= 030a07e441296c372f946cd4065b5d831d8dc40c < 71c610aeb1770302ac9c9e0b9a4ecd37f1311928","Linux 2.6.28"],"published":"2026-09-25","updated":"2026-10-03","sourceUpdated":"2026-10-03T11:18:10.920","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-97931","references":[{"url":"https://git.kernel.org/stable/c/0eb9dd4774af0ac4d1fd105ef2b0a1f6cec06f2f","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/64a87950239867682cde128020e1a47088295e5c","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/6a5f5a5a32c78e67701f1d0f26bc87af68895604","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/71c610aeb1770302ac9c9e0b9a4ecd37f1311928","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/938e8d6cee8d36f24669dfdcd3717e081eb32d64","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/becb89036a1320ef0a77da2d27935ac0704345c4","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/cbc1f954ce67d739d41d1f0757d29850353ebb6a","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/d9c537b14f4982f17b103e3a2cfeee4bee6bc026","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-97931.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-97931"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2541209"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-97931"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-97931"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-97931.mbox"}],"tags":["nvd","cve.org","csaf","vex","red-hat"],"epss":0.00145,"epssPercentile":0.03742,"ingestedAt":"2026-09-25T11:06:38.885Z","slug":"CVE-2026-97931","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nALSA: us122l: Prevent write upgrades for read mappings\n\nThe hwdep mmap callback rejects read-buffer mappings that are initially\nwritable, but leaves VM_MAYWRITE set on mappings created with PROT_READ.\nA process that can open the hwdep node O_RDWR can later use mprotect() to\nmake the mapping writable.\n\nThe read allocation begins with struct usb_stream. Its read_size member is\nused by the fault handler to decide which pages belong to the read buffer.\nThe read VMA intentionally remains expandable because pcm_usb_stream uses\nmremap() after reading that size. Changing read_size first can therefore\nmap and access pages beyond the allocation. The same member is also\nconsumed by usb_stream_free(), where changing it can make\nfree_pages_exact() release pages outside the allocation.\n\nClear VM_MAYWRITE for read-buffer mappings after rejecting an initially\nwritable VMA. This keeps the separate output-buffer mapping writable while\npreventing later permission upgrades.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, … · updated 2026-09-29 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-97931.json)","depth":"twilight","depthScore":39,"depthScoreParts":{"impact":38.5,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":210952,"id":"CVE-2026-97931","ts":1790349118466,"field":"cvss","old":null,"new":"7"},{"seq":210951,"id":"CVE-2026-97931","ts":1790349118466,"field":"severity","old":"none","new":"high"}]}