{"id":"CVE-2026-89743","summary":"misc: nsm: bound the device-reported response length","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nmisc: nsm: bound the device-reported response length\n\nnsm_sendrecv_msg_locked() stores the virtqueue used-ring length reported\nby the NSM device into msg-\u003eresp.len without bounding it to the response\nbuffer. A malicious or buggy backend can report a length larger than the\nresponse buffer; parse_resp_raw() then copies that many bytes out of the\nfixed buffer to user space, disclosing adjacent kernel heap (an\nout-of-bounds read). The request path already floors its length in\nfill_req_raw(); the response path lacks the symmetric check.\n\nClamp the stored length to the size of the response buffer. Well-behaved\ndevices report no more than the posted buffer size, so conforming traffic\nis unaffected.","modified":"2026-09-14T03:46:34.504043762Z","published":"2026-09-11T19:46:49.261Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89743.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/29e634a18957acda11383a15ab98a91c4ae9e294"},{"type":"WEB","url":"https://git.kernel.org/stable/c/2aa0fb9c96f894a9c179a48e7522ea6705800adf"},{"type":"WEB","url":"https://git.kernel.org/stable/c/339f19b9a6171289b0e797deb8bda80b9a1fcc30"},{"type":"WEB","url":"https://git.kernel.org/stable/c/808e530654a5354e6df78863a5d61e4d44e67235"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89743.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89743"},{"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":"b9873755a6c8ccfce79094c4dce9efa3ecb1a749"},{"fixed":"339f19b9a6171289b0e797deb8bda80b9a1fcc30"},{"fixed":"29e634a18957acda11383a15ab98a91c4ae9e294"},{"fixed":"2aa0fb9c96f894a9c179a48e7522ea6705800adf"},{"fixed":"808e530654a5354e6df78863a5d61e4d44e67235"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-89743.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.8.0"},{"fixed":"6.12.109"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.50"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.2.4"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-89743.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H"}]}