{"id":"CVE-2025-21870","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nASoC: SOF: ipc4-topology: Harden loops for looking up ALH copiers\n\nOther, non DAI copier widgets could have the same  stream name (sname) as\nthe ALH copier and in that …","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nASoC: SOF: ipc4-topology: Harden loops for looking up ALH copiers\n\nOther, non DAI copier widgets could have the same  stream name (sname) as\nthe ALH copier and in that …","severity":"high","cvss":7.8,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-476"],"vendor":"linux","product":"linux_kernel","affected":["linux_kernel >= 6.0, < 6.12.17","linux_kernel >= 6.13, < 6.13.5","linux_kernel = 6.14"],"patched":["linux_kernel 6.13.5"],"published":"2025-03-27","updated":"2026-07-30","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2025-21870","references":[{"url":"https://git.kernel.org/stable/c/6fd60136d256b3b948333ebdb3835f41a95ab7ef","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/87c8768a96092ce75cd47fe076db5080db7ac515","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/93c6c2e5801aab09ef1ef99f248f3cd323c3f152","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"tags":["nvd"],"epss":0.002,"epssPercentile":0.1013,"ingestedAt":"2026-07-30T06:53:10.621Z","slug":"CVE-2025-21870","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nASoC: SOF: ipc4-topology: Harden loops for looking up ALH copiers\n\nOther, non DAI copier widgets could have the same  stream name (sname) as\nthe ALH copier and in that case the copier->data is NULL, no alh_data is\nattached, which could lead to NULL pointer dereference.\nWe could check for this NULL pointer in sof_ipc4_prepare_copier_module()\nand avoid the crash, but a similar loop in sof_ipc4_widget_setup_comp_dai()\nwill miscalculate the ALH device count, causing broken audio.\n\nThe correct fix is to harden the matching logic by making sure that the\n1. widget is a DAI widget - so dai = w->private is valid\n2. the dai (and thus the copier) is ALH copier\n\n## Affected\n\n- `linux_kernel >= 6.0, < 6.12.17`\n- `linux_kernel >= 6.13, < 6.13.5`\n- `linux_kernel = 6.14`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `linux_kernel 6.13.5`","depth":"twilight","depthScore":43,"depthScoreParts":{"impact":42.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}