pysec - pysec-2023-133

PYSEC-2023-133

Vulnerability from pysec - Published: 2023-07-25 21:15 - Updated: 2023-08-03 18:27

Details

Vyper is a Pythonic programming language that targets the Ethereum Virtual Machine (EVM). Prior to version 0.3.10, the ecrecover precompile does not fill the output buffer if the signature does not verify. However, the ecrecover builtin will still return whatever is at memory location 0. This means that the if the compiler has been convinced to write to the 0 memory location with specially crafted data (generally, this can happen with a hashmap access or immutable read) just before the ecrecover, a signature check might pass on an invalid signature. Version 0.3.10 contains a patch for this issue.

Severity ?

5.3 (Medium)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/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": "019a37ab98ff53f04fecfadf602b6cd5ac748f7f"
            }
          ],
          "repo": "https://github.com/vyperlang/vyper",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.3.9"
            }
          ],
          "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",
        "0.3.8"
      ]
    }
  ],
  "aliases": [
    "CVE-2023-37902",
    "GHSA-f5x6-7qgp-jhf3"
  ],
  "details": "Vyper is a Pythonic programming language that targets the Ethereum Virtual Machine (EVM). Prior to version 0.3.10, the ecrecover precompile does not fill the output buffer if the signature does not verify. However, the ecrecover builtin will still return whatever is at memory location 0. This means that the if the compiler has been convinced to write to the 0 memory location with specially crafted data (generally, this can happen with a hashmap access or immutable read) just before the ecrecover, a signature check might pass on an invalid signature. Version 0.3.10 contains a patch for this issue.",
  "id": "PYSEC-2023-133",
  "modified": "2023-08-03T18:27:50.332832+00:00",
  "published": "2023-07-25T21:15:00+00:00",
  "references": [
    {
      "type": "EVIDENCE",
      "url": "https://github.com/vyperlang/vyper/security/advisories/GHSA-f5x6-7qgp-jhf3"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/vyperlang/vyper/security/advisories/GHSA-f5x6-7qgp-jhf3"
    },
    {
      "type": "FIX",
      "url": "https://github.com/vyperlang/vyper/commit/019a37ab98ff53f04fecfadf602b6cd5ac748f7f"
    }
  ],
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-F5X6-7QGP-JHF3

Vulnerability from github – Published: 2023-07-25 17:46 – Updated: 2024-11-19 16:44

Summary

ecrecover can return undefined data if signature does not verify

Details

Impact

the ecrecover precompile does not fill the output buffer if the signature does not verify, see https://github.com/ethereum/go-ethereum/blob/b058cf454b3bdc7e770e2b3cec83a0bcb48f55ee/core/vm/contracts.go#L188. however, the ecrecover builtin will still return whatever is at memory location 0.

this means that the if the compiler has been convinced to write to the 0 memory location with specially crafted data (generally, this can happen with a hashmap access or immutable read) just before the ecrecover, a signature check might pass on an invalid signature.

A contract search was performed. Most uses of ecrecover are used for erc2612-style permit implementations, which typically look like:

    assert _owner != empty(address)
    assert block.timestamp <= _deadline

    nonce: uint256 = self.nonces[_owner]
    digest: bytes32 = keccak256(
        concat(   
            b"\x19\x01",
            self.DOMAIN_SEPARATOR,
            keccak256(_abi_encode(PERMIT_TYPEHASH, _owner, _spender, _value, nonce, _deadline))
        )         
    )             
    assert ecrecover(digest, convert(_v, uint256), convert(_r, uint256), convert(_s, uint256)) == _owner

in this case, the immutable PERMIT_TYPEHASH is loaded into ecrecover's output buffer right before ecrecover(), and so the output of ecrecover() here when the signature is invalid will be the value of PERMIT_TYPEHASH. in this case, since PERMIT_TYPEHASH is not a valid address, it will never compare == to _owner, and so the behaviour is exactly the same as if ecrecover() returned 0 in this case.

in general, a contract could have unexpected behavior (i.e. mistakenly pass this style of signature check) if an immutable representing a real address (ex. OWNER) was read right before the ecrecover operation.

Patches

v0.3.10 (with 019a37ab98ff53f04fecfadf602b6cd5ac748f7f and #3586)

Workarounds

Is there a way for users to fix or remediate the vulnerability without upgrading?

References

Are there any links users can visit to find out more?

Severity ?

5.3 (Medium)


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

6.9 (Medium)


                  
                    CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "vyper"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.3.10"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2023-37902"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-252"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2023-07-25T17:46:19Z",
    "nvd_published_at": "2023-07-25T21:15:10Z",
    "severity": "MODERATE"
  },
  "details": "### Impact\nthe ecrecover precompile does not fill the output buffer if the signature does not verify, see https://github.com/ethereum/go-ethereum/blob/b058cf454b3bdc7e770e2b3cec83a0bcb48f55ee/core/vm/contracts.go#L188. however, the ecrecover builtin will still return whatever is at memory location 0.\n\nthis means that the if the compiler has been convinced to write to the 0 memory location with specially crafted data (generally, this can happen with a hashmap access or immutable read) just before the ecrecover, a signature check might pass on an invalid signature.\n\nA contract search was performed. Most uses of `ecrecover` are used for erc2612-style permit implementations, which typically look like:\n\n```vyper\n    assert _owner != empty(address)\n    assert block.timestamp \u003c= _deadline\n                  \n    nonce: uint256 = self.nonces[_owner]\n    digest: bytes32 = keccak256(\n        concat(   \n            b\"\\x19\\x01\",\n            self.DOMAIN_SEPARATOR,\n            keccak256(_abi_encode(PERMIT_TYPEHASH, _owner, _spender, _value, nonce, _deadline))\n        )         \n    )             \n    assert ecrecover(digest, convert(_v, uint256), convert(_r, uint256), convert(_s, uint256)) == _owner\n```\n\nin this case, the immutable `PERMIT_TYPEHASH` is loaded into `ecrecover`\u0027s output buffer right before `ecrecover()`, and so the output of `ecrecover()` here when the signature is invalid will be the value of `PERMIT_TYPEHASH`. in this case, since `PERMIT_TYPEHASH` is not a valid address, it will never compare `==` to `_owner`, and so the behaviour is exactly the same as if `ecrecover()` returned 0 in this case.\n\nin general, a contract could have unexpected behavior (i.e. mistakenly pass this style of signature check) if an immutable representing a real address (ex. `OWNER`) was read right before the `ecrecover` operation.\n\n### Patches\nv0.3.10 (with 019a37ab98ff53f04fecfadf602b6cd5ac748f7f and #3586)\n\n### Workarounds\n_Is there a way for users to fix or remediate the vulnerability without upgrading?_\n\n### References\n_Are there any links users can visit to find out more?_\n",
  "id": "GHSA-f5x6-7qgp-jhf3",
  "modified": "2024-11-19T16:44:35Z",
  "published": "2023-07-25T17:46:19Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/vyperlang/vyper/security/advisories/GHSA-f5x6-7qgp-jhf3"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-37902"
    },
    {
      "type": "WEB",
      "url": "https://github.com/vyperlang/vyper/commit/019a37ab98ff53f04fecfadf602b6cd5ac748f7f"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pypa/advisory-database/tree/main/vulns/vyper/PYSEC-2023-133.yaml"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/vyperlang/vyper"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "ecrecover can return undefined data if signature does not verify"
}

CVE-2023-37902 (GCVE-0-2023-37902)

Vulnerability from cvelistv5 – Published: 2023-07-25 20:05 – Updated: 2024-10-03 18:59

Summary

Severity ?

5.3 (Medium)


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

CWE

CWE-252 - Unchecked Return Value

Assigner

GitHub_M

References

URL

Tags

	https://github.com/vyperlang/vyper/security/advis…	x_refsource_CONFIRM
	https://github.com/vyperlang/vyper/commit/019a37a…	x_refsource_MISC

Impacted products

	Vendor	Product	Version
	vyperlang	vyper	Affected: < 0.3.10

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2024-08-02T17:23:27.794Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "name": "https://github.com/vyperlang/vyper/security/advisories/GHSA-f5x6-7qgp-jhf3",
            "tags": [
              "x_refsource_CONFIRM",
              "x_transferred"
            ],
            "url": "https://github.com/vyperlang/vyper/security/advisories/GHSA-f5x6-7qgp-jhf3"
          },
          {
            "name": "https://github.com/vyperlang/vyper/commit/019a37ab98ff53f04fecfadf602b6cd5ac748f7f",
            "tags": [
              "x_refsource_MISC",
              "x_transferred"
            ],
            "url": "https://github.com/vyperlang/vyper/commit/019a37ab98ff53f04fecfadf602b6cd5ac748f7f"
          }
        ],
        "title": "CVE Program Container"
      },
      {
        "affected": [
          {
            "cpes": [
              "cpe:2.3:a:vyperlang:vyper:*:*:*:*:*:*:*:*"
            ],
            "defaultStatus": "unknown",
            "product": "vyper",
            "vendor": "vyperlang",
            "versions": [
              {
                "lessThan": "0.3.10",
                "status": "affected",
                "version": "0",
                "versionType": "custom"
              }
            ]
          }
        ],
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2023-37902",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2024-10-03T18:58:38.236762Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2024-10-03T18:59:13.773Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "vyper",
          "vendor": "vyperlang",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 0.3.10"
            }
          ]
        }
      ],
      "descriptions": [
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          "value": "Vyper is a Pythonic programming language that targets the Ethereum Virtual Machine (EVM). Prior to version 0.3.10, the ecrecover precompile does not fill the output buffer if the signature does not verify. However, the ecrecover builtin will still return whatever is at memory location 0. This means that the if the compiler has been convinced to write to the 0 memory location with specially crafted data (generally, this can happen with a hashmap access or immutable read) just before the ecrecover, a signature check might pass on an invalid signature. Version 0.3.10 contains a patch for this issue."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 5.3,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "NONE",
            "integrityImpact": "LOW",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-252",
              "description": "CWE-252: Unchecked Return Value",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2023-07-25T20:05:40.615Z",
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      },
      "references": [
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          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/vyperlang/vyper/security/advisories/GHSA-f5x6-7qgp-jhf3"
        },
        {
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          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/vyperlang/vyper/commit/019a37ab98ff53f04fecfadf602b6cd5ac748f7f"
        }
      ],
      "source": {
        "advisory": "GHSA-f5x6-7qgp-jhf3",
        "discovery": "UNKNOWN"
      },
      "title": "Vyper\u0027s ecrecover can return undefined data if signature does not verify"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2023-37902",
    "datePublished": "2023-07-25T20:05:40.615Z",
    "dateReserved": "2023-07-10T17:51:29.610Z",
    "dateUpdated": "2024-10-03T18:59:13.773Z",
    "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-2023-133

GHSA-F5X6-7QGP-JHF3

Impact

Patches

Workarounds

References

CVE-2023-37902 (GCVE-0-2023-37902)

Tags

Sightings

Nomenclature