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TI-2024-16181 Aliases CVE-2024-24560GHSA-gp3w-2v2m-p686

Vyper external calls can overflow return data to return input buffer

Priority MEDIUM 63CWE-119Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
Low · None · None
Fix status
Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and GitHub.

Summary

Vyper is a Pythonic Smart Contract Language for the Ethereum Virtual Machine. When calls to external contracts are made, we write the input buffer starting at byte 28, and allocate the return buffer to start at byte 0 (overlapping with the input buffer). When checking RETURNDATASIZE for dynamic types, the size is compared only to the minimum allowed size for that type, and not to the returned value's length. As a result, malformed return data can cause the contract to mistake data from the input buffer for returndata. When the called contract returns invalid ABIv2 encoded data, the calling contract can read different invalid data (from the dirty buffer) than the called contract returned.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00526 44th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed vyper (PyPI): 0.4.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
vyperlangvyperup to 0.3.10—No fix listedCNA
—vyper (PyPI)before 0.4.00.4.0Patch availableGHSA-gp3w-2v2m-p686
  • vyper Vendorvyperlang Affected up to 0.3.10 Fixed in — No fix listed CNA
  • vyper (PyPI) Vendor— Affected before 0.4.0 Fixed in 0.4.0 Patch available GHSA-gp3w-2v2m-p686

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:vyperlang:vyper:*:*:*:*:*:python:*:*up to 0.3.10Vulnerablevyperlang
  • cpe:2.3:a:vyperlang:vyper:*:*:*:*:*:python:*:* Versions up to 0.3.10 Vulnerable ·vyperlang

Remediation

  • Fix · GHSA-gp3w-2v2m-p686 vyper (PyPI) Fixed in 0.4.0 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2024-24560
  2. 2026-10-03 Alias added: GHSA-gp3w-2v2m-p686

References

Exploit 1

Advisory 1

Other 2

  • TI-2024-16182 Vyper bounds check on built-in `slice()` function can be overflowed CVSS 3.1CRITICAL 9.8
  • TI-2024-14992 concat built-in can corrupt memory in vyper CVSS 3.1CRITICAL 9.8
  • TI-2024-16184 Vyper array negative index vulnerability CVSS 3.1CRITICAL 9.8
  • TI-2022-08657 Integer bounds error in Vyper CVSS 3.1CRITICAL 9.8
  • TI-2022-11796 Multiple evaluation of contract address in call in vyper CVSS 3.1HIGH 8.2
  • TI-2024-21531 vyper performs double eval of the argument of sqrt CVSS 3.1MEDIUM 5.3
See all 37 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences