{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "e0bbb53843b5fdfe464b099217e3b9d97e8a75d7"
            },
            {
              "fixed": "e9ae8e86eed68bea5d2670eadf61938a43bd2263"
            },
            {
              "fixed": "64e3ec7a71d3b715e2567f19f64207f04999bb0c"
            },
            {
              "fixed": "863fa63fd1491f201ac819f805a8db98d2a32c3d"
            },
            {
              "fixed": "e71a3dc5b8d2ea4d9cfbdb135d6b7777de84212e"
            },
            {
              "fixed": "31c81b376e5f058c7f2c94f69719cf7caec2fc3f"
            },
            {
              "fixed": "a776afa89424570bfa637ebf812ca281a5732904"
            },
            {
              "fixed": "343aa5275484d627c921a42e8e115cae366be5de"
            },
            {
              "fixed": "abb81e5ce7d995baa41556b8125fa59e28ba3be8"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "last_affected": "108681048cf728a8570e036c34ebd7daa43133b4"
            },
            {
              "last_affected": "3a5837c692918c229baf63fe7950965d27c48ac2"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "5.4.47"
            },
            {
              "fixed": "5.5"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "5.6.19"
            },
            {
              "fixed": "5.7"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "5.7.0"
            },
            {
              "fixed": "5.10.270"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.11.0"
            },
            {
              "fixed": "5.15.221"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.188"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.157"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.110"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.52"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.2.6"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/93xxx/CVE-2026-93167.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\ncsky: Fix a4/a5 restoration in syscall trace path\n\nThe syscall trace path reloads syscall arguments from pt_regs before\ncalling the syscall handler. On C-SKY ABIv2, the 5th and 6th syscall\narguments are prepared as stack arguments before invoking syscallid.\n\nThe current code adjusts sp before loading LSAVE_A4 and LSAVE_A5. Since\nthose offsets are relative to the original pt_regs base, loading them\nafter changing sp fetches the wrong slots. As a result, traced syscalls\nthat use the 5th or 6th argument may receive corrupted arguments.\n\nThis is visible with mmap2(), which takes six arguments. A small\nPTRACE_SYSCALL reproducer opens a file and maps one page with:\n\n  mmap(NULL, 4096, PROT_READ | PROT_EXEC, MAP_PRIVATE, fd, 0)\n\nBefore the fix, the traced child fails the mmap and exits with 12.\nAfter the fix, the mapping succeeds and the child exits with 0.\n\nFix the trace path by loading a4/a5 from pt_regs before changing sp.\n\nTested on: ck860f, linux-4.19.15, C-SKY abiv2",
  "id": "CVE-2026-93167",
  "modified": "2026-09-18T03:30:47.039872489Z",
  "published": "2026-09-17T16:11:59.234Z",
  "references": [
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/31c81b376e5f058c7f2c94f69719cf7caec2fc3f"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/343aa5275484d627c921a42e8e115cae366be5de"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/64e3ec7a71d3b715e2567f19f64207f04999bb0c"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/863fa63fd1491f201ac819f805a8db98d2a32c3d"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/a776afa89424570bfa637ebf812ca281a5732904"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/abb81e5ce7d995baa41556b8125fa59e28ba3be8"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/e71a3dc5b8d2ea4d9cfbdb135d6b7777de84212e"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/e9ae8e86eed68bea5d2670eadf61938a43bd2263"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/93xxx/CVE-2026-93167.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-93167"
    }
  ],
  "schema_version": "1.9.0",
  "summary": "csky: Fix a4/a5 restoration in syscall trace path"
}