{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "17519819926211e6b2834e00e4554bec0daf22ac"
            },
            {
              "fixed": "4105dd76bc8ad6529d47157ef0565cb84ca6676c"
            },
            {
              "fixed": "594bfc4947c4fcabba1318d8384c61a29a6b89fb"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/57xxx/CVE-2024-57877.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\narm64: ptrace: fix partial SETREGSET for NT_ARM_POE\n\nCurrently poe_set() doesn't initialize the temporary 'ctrl' variable,\nand a SETREGSET call with a length of zero will leave this\nuninitialized. Consequently an arbitrary value will be written back to\ntarget-\u003ethread.por_el0, potentially leaking up to 64 bits of memory from\nthe kernel stack. The read is limited to a specific slot on the stack,\nand the issue does not provide a write mechanism.\n\nFix this by initializing the temporary value before copying the regset\nfrom userspace, as for other regsets (e.g. NT_PRSTATUS, NT_PRFPREG,\nNT_ARM_SYSTEM_CALL). In the case of a zero-length write, the existing\ncontents of POR_EL1 will be retained.\n\nBefore this patch:\n\n| # ./poe-test\n| Attempting to write NT_ARM_POE::por_el0 = 0x900d900d900d900d\n| SETREGSET(nt=0x40f, len=8) wrote 8 bytes\n|\n| Attempting to read NT_ARM_POE::por_el0\n| GETREGSET(nt=0x40f, len=8) read 8 bytes\n| Read NT_ARM_POE::por_el0 = 0x900d900d900d900d\n|\n| Attempting to write NT_ARM_POE (zero length)\n| SETREGSET(nt=0x40f, len=0) wrote 0 bytes\n|\n| Attempting to read NT_ARM_POE::por_el0\n| GETREGSET(nt=0x40f, len=8) read 8 bytes\n| Read NT_ARM_POE::por_el0 = 0xffff8000839c3d50\n\nAfter this patch:\n\n| # ./poe-test\n| Attempting to write NT_ARM_POE::por_el0 = 0x900d900d900d900d\n| SETREGSET(nt=0x40f, len=8) wrote 8 bytes\n|\n| Attempting to read NT_ARM_POE::por_el0\n| GETREGSET(nt=0x40f, len=8) read 8 bytes\n| Read NT_ARM_POE::por_el0 = 0x900d900d900d900d\n|\n| Attempting to write NT_ARM_POE (zero length)\n| SETREGSET(nt=0x40f, len=0) wrote 0 bytes\n|\n| Attempting to read NT_ARM_POE::por_el0\n| GETREGSET(nt=0x40f, len=8) read 8 bytes\n| Read NT_ARM_POE::por_el0 = 0x900d900d900d900d",
  "id": "CVE-2024-57877",
  "modified": "2026-04-01T23:08:15.400967849Z",
  "published": "2025-01-11T14:49:03.297Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/4105dd76bc8ad6529d47157ef0565cb84ca6676c"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/594bfc4947c4fcabba1318d8384c61a29a6b89fb"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/57xxx/CVE-2024-57877.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-57877"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.7.3",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "arm64: ptrace: fix partial SETREGSET for NT_ARM_POE"
}