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TI-2024-21375 Aliases CVE-2024-32481GHSA-ppx5-q359-pvwj

vyper's range(start, start + N) reverts for negative numbers

Priority MEDIUM 63CWE-681Published · Updated

Key facts

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

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

Summary

Vyper is a pythonic Smart Contract Language for the Ethereum virtual machine. Starting in version 0.3.8 and prior to version 0.4.0b1, when looping over a `range` of the form `range(start, start + N)`, if `start` is negative, the execution will always revert. This issue is caused by an incorrect assertion inserted by the code generation of the range `stmt.parse_For_range()`. The issue arises when `start` is signed, instead of using `sle`, `le` is used and `start` is interpreted as an unsigned integer for the comparison. If it is a negative number, its 255th bit is set to `1` and is hence interpreted as a very large unsigned integer making the assertion always fail. Any contract having a `range(start, start + N)` where `start` is a signed integer with the possibility for `start` to be negative is affected. If a call goes through the loop while supplying a negative `start` the execution will revert. Version 0.4.0b1 fixes the issue.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00791 56th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed vyper (vyperlang): 0.4.0b1vyper (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
vyperlangvyper0.3.8 to before 0.4.0b10.4.0b1Patch availableCNA
—vyper (PyPI)0.3.8 to before 0.4.00.4.0Patch availableGHSA-ppx5-q359-pvwj
  • vyper Vendorvyperlang Affected 0.3.8 to before 0.4.0b1 Fixed in 0.4.0b1 Patch available CNA
  • vyper (PyPI) Vendor— Affected 0.3.8 to before 0.4.0 Fixed in 0.4.0 Patch available GHSA-ppx5-q359-pvwj

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:a:vyperlang:vyper:*:*:*:*:*:python:*:*0.3.8 – 0.3.10Vulnerablevyperlang
cpe:2.3:a:vyperlang:vyper:0.4.0:-:*:*:*:python:*:*0.4.0Vulnerablevyperlang
  • cpe:2.3:a:vyperlang:vyper:*:*:*:*:*:python:*:* Versions 0.3.8 – 0.3.10 Vulnerable ·vyperlang
  • cpe:2.3:a:vyperlang:vyper:0.4.0:-:*:*:*:python:*:* Versions 0.4.0 Vulnerable ·vyperlang

Remediation

  • Fix · CNA vyper (vyperlang) Fixed in 0.4.0b1
  • Fix · GHSA-ppx5-q359-pvwj vyper (PyPI) Fixed in 0.4.0 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2024-32481
  2. 2026-10-03 Alias added: GHSA-ppx5-q359-pvwj

References

Exploit 1

Patch 2

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