{"id":"CVE-2026-68277","summary":"drm/dp/mst: fix OOB reads on 2-byte fields in sideband reply parsers","details":"In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/dp/mst: fix OOB reads on 2-byte fields in sideband reply parsers\n\nThree sideband reply parsers read 16-bit fields as:\n\n  val = (raw-\u003emsg[idx] \u003c\u003c 8) | (raw-\u003emsg[idx+1]);\n\nand check bounds only after the fact. When idx == raw-\u003ecurlen,\nraw-\u003emsg[idx+1] reads one byte past the received message data into\nthe following struct fields (curchunk_len, curchunk_idx, curlen).\n\nAffected functions:\n - drm_dp_sideband_parse_enum_path_resources_ack()\n   full_payload_bw_number and avail_payload_bw_number fields\n - drm_dp_sideband_parse_allocate_payload_ack()\n   allocated_pbn field\n - drm_dp_sideband_parse_query_payload_ack()\n   allocated_pbn field\n\nFix by using a single combined check (idx + 2 \u003e curlen) before each\n2-byte read. Since the check is strictly tighter than idx \u003e curlen,\nno separate step is needed.\n\n[added fixes tag]","modified":"2026-08-12T04:19:22.250317965Z","published":"2026-08-10T12:01:53.085Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/68xxx/CVE-2026-68277.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/0bcd7675c69a2462a8531fcd9e4d096e9c7ec5df"},{"type":"WEB","url":"https://git.kernel.org/stable/c/68a624416d1dd481b3e5b7ea0e8a070a9b8a2c73"},{"type":"WEB","url":"https://git.kernel.org/stable/c/6b89ba3dba2f583626fb693e47e951ffb8bf591f"},{"type":"WEB","url":"https://git.kernel.org/stable/c/bdf0508b1e6785d4a8982c637e97e68d60b47d7b"},{"type":"WEB","url":"https://git.kernel.org/stable/c/d5c70523cafa26ad2c7a37b612849abe2683baa8"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/68xxx/CVE-2026-68277.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-68277"},{"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":"ad7f8a1f9ced7f049f9b66d588723f243a7034cd"},{"fixed":"bdf0508b1e6785d4a8982c637e97e68d60b47d7b"},{"fixed":"0bcd7675c69a2462a8531fcd9e4d096e9c7ec5df"},{"fixed":"d5c70523cafa26ad2c7a37b612849abe2683baa8"},{"fixed":"68a624416d1dd481b3e5b7ea0e8a070a9b8a2c73"},{"fixed":"6b89ba3dba2f583626fb693e47e951ffb8bf591f"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-68277.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.17.0"},{"fixed":"6.6.148"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.101"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.42"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.1.6"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-68277.json"}}],"schema_version":"1.9.0"}