pysec - pysec-2023-307

PYSEC-2023-307

Vulnerability from pysec - Published: 2023-12-13 20:15 - Updated: 2024-11-21 14:23

Details

Vyper is a Pythonic Smart Contract Language for the Ethereum Virtual Machine (EVM). Contracts containing large arrays might underallocate the number of slots they need by 1. Prior to v0.3.8, the calculation to determine how many slots a storage variable needed used math.ceil(type_.size_in_bytes / 32). The intermediate floating point step can produce a rounding error if there are enough bits set in the IEEE-754 mantissa. Roughly speaking, if type_.size_in_bytes is large (> 2**46), and slightly less than a power of 2, the calculation can overestimate how many slots are needed by 1. If type_.size_in_bytes is slightly more than a power of 2, the calculation can underestimate how many slots are needed by 1. This issue is patched in version 0.3.8.

Severity ?

7.5 (High)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Impacted products

Name	purl
vyper	pkg:pypi/vyper

Aliases

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "vyper",
        "purl": "pkg:pypi/vyper"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0bb7203b584e771b23536ba065a6efda457161bb"
            }
          ],
          "repo": "https://github.com/vyperlang/vyper",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.3.8"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.1.0b1",
        "0.1.0b10",
        "0.1.0b11",
        "0.1.0b12",
        "0.1.0b13",
        "0.1.0b14",
        "0.1.0b15",
        "0.1.0b16",
        "0.1.0b17",
        "0.1.0b2",
        "0.1.0b3",
        "0.1.0b4",
        "0.1.0b5",
        "0.1.0b6",
        "0.1.0b7",
        "0.1.0b8",
        "0.1.0b9",
        "0.2.1",
        "0.2.10",
        "0.2.11",
        "0.2.12",
        "0.2.13",
        "0.2.14",
        "0.2.15",
        "0.2.16",
        "0.2.2",
        "0.2.3",
        "0.2.4",
        "0.2.5",
        "0.2.6",
        "0.2.7",
        "0.2.8",
        "0.2.9",
        "0.3.0",
        "0.3.1",
        "0.3.2",
        "0.3.3",
        "0.3.4",
        "0.3.5",
        "0.3.6",
        "0.3.7"
      ]
    }
  ],
  "aliases": [
    "CVE-2023-46247",
    "GHSA-6m97-7527-mh74"
  ],
  "details": "Vyper is a Pythonic Smart Contract Language for the Ethereum Virtual Machine (EVM). Contracts containing large arrays might underallocate the number of slots they need by 1. Prior to v0.3.8, the calculation to determine how many slots a storage variable needed used `math.ceil(type_.size_in_bytes / 32)`. The intermediate floating point step can produce a rounding error if there are enough bits set in the IEEE-754 mantissa. Roughly speaking, if `type_.size_in_bytes` is large (\u003e 2**46), and slightly less than a power of 2, the calculation can overestimate how many slots are needed by 1. If `type_.size_in_bytes` is slightly more than a power of 2, the calculation can underestimate how many slots are needed by 1. This issue is patched in version 0.3.8.",
  "id": "PYSEC-2023-307",
  "modified": "2024-11-21T14:23:02.808922+00:00",
  "published": "2023-12-13T20:15:00+00:00",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/vyperlang/vyper/security/advisories/GHSA-6m97-7527-mh74"
    },
    {
      "type": "FIX",
      "url": "https://github.com/vyperlang/vyper/commit/0bb7203b584e771b23536ba065a6efda457161bb"
    },
    {
      "type": "WEB",
      "url": "https://github.com/vyperlang/vyper/blob/6020b8bbf66b062d299d87bc7e4eddc4c9d1c157/vyper/semantics/validation/data_positions.py#L197"
    }
  ],
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-6M97-7527-MH74

Vulnerability from github – Published: 2023-12-13 13:18 – Updated: 2024-11-22 20:41

Summary

incorrect storage layout for contracts containing large arrays

Details

Impact

contracts containing large arrays might underallocate the number of slots they need. prior to v0.3.8, the calculation to determine how many slots a storage variable needed used math.ceil(type_.size_in_bytes / 32):

https://github.com/vyperlang/vyper/blob/6020b8bbf66b062d299d87bc7e4eddc4c9d1c157/vyper/semantics/validation/data_positions.py#L197

the intermediate floating point step can produce a rounding error if there are enough bits set in the IEEE-754 mantissa. roughly speaking, if type_.size_in_bytes is large (> 2**46), and slightly less than a power of 2, the calculation can overestimate how many slots are needed. if type_.size_in_bytes is slightly more than a power of 2, the calculation can underestimate how many slots are needed.

the following two example contracts can result in overwriting of the variable vulnerable:

large_array: address[2**64 + 1]  # type_.size_in_bytes == 32 * (2**64 + 1); math.ceil(type_.size_in_bytes / 32) < 2**64 + 1
vulnerable: uint256

# writing to self.large_array[2**64] will overwrite self.vulnerable

large_dynarray: DynArray[address, 2**64]  # Dynarray has a length word in front, its size in bytes is 32 * (2**64 + 1)
vulnerable: uint256

# writing to self.large_dynarray[2**64 - 1] will overwrite self.vulnerable

note that in the latter case, the risk of vulnerable being overwritten is relatively small, since it would cost roughly $1.45 million trillion USD at today's gas prices (gas price 20gwei, ETH ~= $1800) in order to extend the DynArray to its full container size.

Patches

patched by v0.3.8, specifically in commit https://github.com/vyperlang/vyper/commit/0bb7203b584e771b23536ba065a6efda457161bb.

Severity ?

7.5 (High)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 0.3.7"
      },
      "package": {
        "ecosystem": "PyPI",
        "name": "vyper"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.3.8"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2023-46247"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-193"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2023-12-13T13:18:52Z",
    "nvd_published_at": "2023-12-13T20:15:49Z",
    "severity": "HIGH"
  },
  "details": "### Impact\ncontracts containing large arrays might underallocate the number of slots they need. prior to v0.3.8, the calculation to determine how many slots a storage variable needed used `math.ceil(type_.size_in_bytes / 32)`:\n\nhttps://github.com/vyperlang/vyper/blob/6020b8bbf66b062d299d87bc7e4eddc4c9d1c157/vyper/semantics/validation/data_positions.py#L197\n\nthe intermediate floating point step can produce a rounding error if there are enough bits set in the IEEE-754 mantissa. roughly speaking, if `type_.size_in_bytes` is large (\u003e 2**46), and slightly less than a power of 2, the calculation can overestimate how many slots are needed. if `type_.size_in_bytes` is slightly more than a power of 2, the calculation can underestimate how many slots are needed.\n\nthe following two example contracts can result in overwriting of the variable `vulnerable`:\n```vyper\nlarge_array: address[2**64 + 1]  # type_.size_in_bytes == 32 * (2**64 + 1); math.ceil(type_.size_in_bytes / 32) \u003c 2**64 + 1\nvulnerable: uint256\n\n# writing to self.large_array[2**64] will overwrite self.vulnerable\n```\n```vyper\nlarge_dynarray: DynArray[address, 2**64]  # Dynarray has a length word in front, its size in bytes is 32 * (2**64 + 1)\nvulnerable: uint256\n\n# writing to self.large_dynarray[2**64 - 1] will overwrite self.vulnerable\n```\n\nnote that in the latter case, the risk of `vulnerable` being overwritten is relatively small, since it would cost roughly $1.45 million trillion USD at today\u0027s gas prices (gas price 20gwei, ETH ~= $1800) in order to extend the DynArray to its full container size.\n\n### Patches\npatched by v0.3.8, specifically in commit https://github.com/vyperlang/vyper/commit/0bb7203b584e771b23536ba065a6efda457161bb.",
  "id": "GHSA-6m97-7527-mh74",
  "modified": "2024-11-22T20:41:02Z",
  "published": "2023-12-13T13:18:52Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/vyperlang/vyper/security/advisories/GHSA-6m97-7527-mh74"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-46247"
    },
    {
      "type": "WEB",
      "url": "https://github.com/vyperlang/vyper/commit/0bb7203b584e771b23536ba065a6efda457161bb"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pypa/advisory-database/tree/main/vulns/vyper/PYSEC-2023-307.yaml"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/vyperlang/vyper"
    },
    {
      "type": "WEB",
      "url": "https://github.com/vyperlang/vyper/blob/6020b8bbf66b062d299d87bc7e4eddc4c9d1c157/vyper/semantics/validation/data_positions.py#L197"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "incorrect storage layout for contracts containing large arrays"
}

CVE-2023-46247 (GCVE-0-2023-46247)

Vulnerability from cvelistv5 – Published: 2023-12-13 19:39 – Updated: 2024-08-02 20:37

Summary

Vyper is a Pythonic Smart Contract Language for the Ethereum Virtual Machine (EVM). Contracts containing large arrays might underallocate the number of slots they need by 1. Prior to v0.3.8, the calculation to determine how many slots a storage variable needed used `math.ceil(type_.size_in_bytes / 32)`. The intermediate floating point step can produce a rounding error if there are enough bits set in the IEEE-754 mantissa. Roughly speaking, if `type_.size_in_bytes` is large (> 2**46), and slightly less than a power of 2, the calculation can overestimate how many slots are needed by 1. If `type_.size_in_bytes` is slightly more than a power of 2, the calculation can underestimate how many slots are needed by 1. This issue is patched in version 0.3.8.

Severity ?

7.5 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

CWE

CWE-193 - Off-by-one Error
CWE-682 - Incorrect Calculation

Assigner

GitHub_M

References

URL

Tags

	https://github.com/vyperlang/vyper/security/advis…	x_refsource_CONFIRM
	https://github.com/vyperlang/vyper/commit/0bb7203…	x_refsource_MISC
	https://github.com/vyperlang/vyper/blob/6020b8bbf…	x_refsource_MISC

Impacted products

	Vendor	Product	Version
	vyperlang	vyper	Affected: < 0.3.8

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2024-08-02T20:37:40.156Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "name": "https://github.com/vyperlang/vyper/security/advisories/GHSA-6m97-7527-mh74",
            "tags": [
              "x_refsource_CONFIRM",
              "x_transferred"
            ],
            "url": "https://github.com/vyperlang/vyper/security/advisories/GHSA-6m97-7527-mh74"
          },
          {
            "name": "https://github.com/vyperlang/vyper/commit/0bb7203b584e771b23536ba065a6efda457161bb",
            "tags": [
              "x_refsource_MISC",
              "x_transferred"
            ],
            "url": "https://github.com/vyperlang/vyper/commit/0bb7203b584e771b23536ba065a6efda457161bb"
          },
          {
            "name": "https://github.com/vyperlang/vyper/blob/6020b8bbf66b062d299d87bc7e4eddc4c9d1c157/vyper/semantics/validation/data_positions.py#L197",
            "tags": [
              "x_refsource_MISC",
              "x_transferred"
            ],
            "url": "https://github.com/vyperlang/vyper/blob/6020b8bbf66b062d299d87bc7e4eddc4c9d1c157/vyper/semantics/validation/data_positions.py#L197"
          }
        ],
        "title": "CVE Program Container"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "vyper",
          "vendor": "vyperlang",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 0.3.8"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Vyper is a Pythonic Smart Contract Language for the Ethereum Virtual Machine (EVM). Contracts containing large arrays might underallocate the number of slots they need by 1. Prior to v0.3.8, the calculation to determine how many slots a storage variable needed used `math.ceil(type_.size_in_bytes / 32)`. The intermediate floating point step can produce a rounding error if there are enough bits set in the IEEE-754 mantissa. Roughly speaking, if `type_.size_in_bytes` is large (\u003e 2**46), and slightly less than a power of 2, the calculation can overestimate how many slots are needed by 1. If `type_.size_in_bytes` is slightly more than a power of 2, the calculation can underestimate how many slots are needed by 1. This issue is patched in version 0.3.8."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 7.5,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "NONE",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-193",
              "description": "CWE-193: Off-by-one Error",
              "lang": "en",
              "type": "CWE"
            }
          ]
        },
        {
          "descriptions": [
            {
              "cweId": "CWE-682",
              "description": "CWE-682: Incorrect Calculation",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2023-12-13T19:39:22.626Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/vyperlang/vyper/security/advisories/GHSA-6m97-7527-mh74",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/vyperlang/vyper/security/advisories/GHSA-6m97-7527-mh74"
        },
        {
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          ],
          "url": "https://github.com/vyperlang/vyper/commit/0bb7203b584e771b23536ba065a6efda457161bb"
        },
        {
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          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/vyperlang/vyper/blob/6020b8bbf66b062d299d87bc7e4eddc4c9d1c157/vyper/semantics/validation/data_positions.py#L197"
        }
      ],
      "source": {
        "advisory": "GHSA-6m97-7527-mh74",
        "discovery": "UNKNOWN"
      },
      "title": "Vyper has incorrect storage layout for contracts containing large arrays"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2023-46247",
    "datePublished": "2023-12-13T19:39:22.626Z",
    "dateReserved": "2023-10-19T20:34:00.948Z",
    "dateUpdated": "2024-08-02T20:37:40.156Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.1"
}

Sightings

Author	Source	Type	Date

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

PYSEC-2023-307

GHSA-6M97-7527-MH74

Impact

Patches

CVE-2023-46247 (GCVE-0-2023-46247)

Tags

Sightings

Nomenclature