Vulnerability-Lookup

GHSA-2R3X-4MRV-MCXF

Vulnerability from github – Published: 2026-10-06 15:22 – Updated: 2026-10-06 15:22

Summary

Vyper: Memory corruption using function calls within tuples / nested calls

Details

Impact

When performing a function call inside a tuple or as an argument inside another function call, there is a memory corruption issue that occurs because of an incorrect pointer to the the tip of the stack.

Example code:

@internal
def _foo(a: uint256, b: uint256, c: uint256) -> (uint256, uint256, uint256, uint256, uint256):
    return 1, a, b, c, 5

@internal
def _foo2() -> uint256:
    a: uint256[10] = [6,7,8,9,10,11,12,13,15,16]
    return 4

@external
def foo() -> (uint256, uint256, uint256, uint256, uint256):
    return self._foo(2, 3, self._foo2())

Please see #2186 for further information

Patches

This problem was fixed in #2186, and released as a part of v0.2.6.

Severity

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

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{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "vyper"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.2.6"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [],
  "database_specific": {
    "cwe_ids": [
      "CWE-129"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-10-06T15:22:29Z",
    "nvd_published_at": null,
    "severity": "MODERATE"
  },
  "details": "### Impact\nWhen performing a function call inside a tuple or as an argument inside another function call, there is a memory corruption issue that occurs because of an incorrect pointer to the the tip of the stack.\n\nExample code:\n```python\n@internal\ndef _foo(a: uint256, b: uint256, c: uint256) -\u003e (uint256, uint256, uint256, uint256, uint256):\n    return 1, a, b, c, 5\n\n@internal\ndef _foo2() -\u003e uint256:\n    a: uint256[10] = [6,7,8,9,10,11,12,13,15,16]\n    return 4\n\n@external\ndef foo() -\u003e (uint256, uint256, uint256, uint256, uint256):\n    return self._foo(2, 3, self._foo2())\n```\n\nPlease see #2186 for further information\n\n### Patches\nThis problem was fixed in #2186, and released as a part of [`v0.2.6`](https://github.com/vyperlang/vyper/releases/tag/v0.2.6).",
  "id": "GHSA-2r3x-4mrv-mcxf",
  "modified": "2026-10-06T15:22:29Z",
  "published": "2026-10-06T15:22:29Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/vyperlang/vyper/security/advisories/GHSA-2r3x-4mrv-mcxf"
    },
    {
      "type": "WEB",
      "url": "https://github.com/vyperlang/vyper/pull/2186"
    },
    {
      "type": "WEB",
      "url": "https://github.com/vyperlang/vyper/commit/74ba67d4bec5f8be4f05759e37d2bfb1463e0441"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/vyperlang/vyper"
    },
    {
      "type": "WEB",
      "url": "https://github.com/vyperlang/vyper/releases/tag/v0.2.6"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "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": "Vyper: Memory corruption using function calls within tuples / nested calls"
}

Sightings

Author	Source	Type	Date	Other

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.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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