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OESA-2024-1120 (CVE-2023-40547)

Vulnerability from osv_openeuler – Published: 2024-02-02 11:06 – Updated: 2026-08-06 11:06 – Source website
VLAI
Summary
shim security update
Details

Initial UEFI bootloader that handles chaining to a trusted full \ bootloader under secure boot environments.

Security Fix(es):

A remote code execution vulnerability was found in Shim. The Shim boot support trusts attacker-controlled values when parsing an HTTP response. This flaw allows an attacker to craft a specific malicious HTTP request, leading to a completely controlled out-of-bounds write primitive and complete system compromise.(CVE-2023-40547)

A buffer overflow was found in Shim in the 32-bit system. The overflow happens due to an addition operation involving a user-controlled value parsed from the PE binary being used by Shim. This value is further used for memory allocation operations, leading to a heap-based buffer overflow. This flaw causes memory corruption and can lead to a crash or data integrity issues during the boot phase.(CVE-2023-40548)

An out-of-bounds read flaw was found in Shim due to the lack of proper boundary verification during the load of a PE binary. This flaw allows an attacker to load a crafted PE binary, triggering the issue and crashing Shim, resulting in a denial of service.(CVE-2023-40549)

An out-of-bounds read flaw was found in Shim when it tried to validate the SBAT information. This issue may expose sensitive data during the system's boot phase.(CVE-2023-40550)

A flaw was found in the MZ binary format in Shim. An out-of-bounds read may occur, leading to a crash or possible exposure of sensitive data during the system's boot phase.(CVE-2023-40551)

Severity
8.3 (High)
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "aarch64": [
          "shim-debuginfo-15.6-19.oe2203sp3.aarch64.rpm",
          "shim-15.6-19.oe2203sp3.aarch64.rpm",
          "shim-debugsource-15.6-19.oe2203sp3.aarch64.rpm"
        ],
        "src": [
          "shim-15.6-19.oe2203sp3.src.rpm"
        ],
        "x86_64": [
          "shim-debuginfo-15.6-19.oe2203sp3.x86_64.rpm",
          "shim-15.6-19.oe2203sp3.x86_64.rpm",
          "shim-debugsource-15.6-19.oe2203sp3.x86_64.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:22.03-LTS-SP3",
        "name": "shim",
        "purl": "pkg:rpm/openEuler/shim\u0026distro=openEuler-22.03-LTS-SP3"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "15.6-19.oe2203sp3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "severity": "High"
  },
  "details": "Initial UEFI bootloader that handles chaining to a trusted full \\ bootloader under secure boot environments.\r\n\r\nSecurity Fix(es):\r\n\r\nA remote code execution vulnerability was found in Shim. The Shim boot support trusts attacker-controlled values when parsing an HTTP response. This flaw allows an attacker to craft a specific malicious HTTP request, leading to a completely controlled out-of-bounds write primitive and complete system compromise.(CVE-2023-40547)\r\n\r\nA buffer overflow was found in Shim in the 32-bit system. The overflow happens due to an addition operation involving a user-controlled value parsed from the PE binary being used by Shim. This value is further used for memory allocation operations, leading to a heap-based buffer overflow. This flaw causes memory corruption and can lead to a crash or data integrity issues during the boot phase.(CVE-2023-40548)\r\n\r\nAn out-of-bounds read flaw was found in Shim due to the lack of proper boundary verification during the load of a PE binary. This flaw allows an attacker to load a crafted PE binary, triggering the issue and crashing Shim, resulting in a denial of service.(CVE-2023-40549)\r\n\r\nAn out-of-bounds read flaw was found in Shim when it tried to validate the SBAT information. This issue may expose sensitive data during the system\u0026apos;s boot phase.(CVE-2023-40550)\r\n\r\nA flaw was found in the MZ binary format in Shim. An out-of-bounds read may occur, leading to a crash or possible exposure of sensitive data during the system\u0026apos;s boot phase.(CVE-2023-40551)",
  "id": "OESA-2024-1120",
  "modified": "2026-08-06T11:06:34Z",
  "published": "2024-02-02T11:06:34Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.openeuler.org/en/security/safety-bulletin/detail.html?id=openEuler-SA-2024-1120"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-40547"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-40548"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-40549"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-40550"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-40551"
    }
  ],
  "schema_version": "1.7.2",
  "severity": [
    {
      "score": "CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "shim security update",
  "upstream": [
    "CVE-2023-40547",
    "CVE-2023-40548",
    "CVE-2023-40549",
    "CVE-2023-40550",
    "CVE-2023-40551"
  ]
}



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