{"id":"CVE-2026-68293","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-68293","summary":"net/mlx5: Fix MCIA register buffer overflow on 32 dword reads","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/mlx5: Fix MCIA register buffer overflow on 32 dword reads\n\nThe MCIA register can return up to 32 dwords (128 bytes) when the device\nadvertises the mcia_32dwords capability, but struct\nmlx5_ifc_mcia_reg_bits only defines dword_0..11, leaving room for just\n12 dwords (48 bytes) of data.\n\nmlx5_query_mcia() clamps the read size to mlx5_mcia_max_bytes() and then\nmemcpy()s that many bytes out of the register, potentially reading past\nthe end of the 'out' buffer. On kernels built with FORTIFY_SOURCE this\nis caught as a buffer overflow while reading the module EEPROM via\nethtool:\n\n  detected buffer overflow in memcpy\n  kernel BUG at lib/string_helpers.c:1048!\n  RIP: 0010:fortify_panic+0x13/0x20\n  Call Trace:\n   mlx5_query_mcia.isra.0+0x200/0x210 [mlx5_core]\n   mlx5_query_module_eeprom_by_page+0x4a/0xa0 [mlx5_core]\n   mlx5e_get_module_eeprom_by_page+0xbb/0x120 [mlx5_core]\n   eeprom_prepare_data+0xf3/0x170\n   ethnl_default_doit+0xf1/0x3b0\n\nExtend the mcia_reg layout to 32 dwords.","published":"2026-08-10T12:02:26.414Z","modified":"2026-08-14T04:04:00.379553112Z","cvss":{"score":7.1,"severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[{"ecosystem":"Linux","name":"Kernel","fixedVersion":"6.12.101"}],"fix":null,"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/11c057d23465c7a5817a7284c896d19d54c0b616"},{"type":"WEB","url":"https://git.kernel.org/stable/c/5be4eebd5a3a198dab0adcd550e1cadca79bdfed"},{"type":"WEB","url":"https://git.kernel.org/stable/c/87b39a8c875ca744b7de69af0a8ef8874cffccf1"},{"type":"WEB","url":"https://git.kernel.org/stable/c/88b2a16ddac3357e3f1d528e758b51e2c945d546"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/68xxx/CVE-2026-68293.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-68293"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-14T04:04:00.379553112Z"}}