CVE-2025-47774 (GCVE-0-2025-47774)

Vulnerability from cvelistv5 – Published: 2025-05-15 17:38 – Updated: 2025-05-15 18:33
VLAI
Title
Vyper's `slice()` may elide side-effects when output length is 0
Summary
Vyper is the Pythonic Programming Language for the Ethereum Virtual Machine. In versions up to and including 0.4.2rc1, the `slice()` builtin can elide side effects when the output length is 0, and the source bytestring is a builtin (`msg.data` or `<address>.code`). The reason is that for these source locations, the check that `length >= 1` is skipped. The result is that a 0-length bytestring constructed with slice can be passed to `make_byte_array_copier`, which elides evaluation of its source argument when the max length is 0. The impact is that side effects in the `start` argument may be elided when the `length` argument is 0, e.g. `slice(msg.data, self.do_side_effect(), 0)`. The fix in pull request 4645 disallows any invocation of `slice()` with length 0, including for the ad hoc locations discussed in this advisory. The fix is expected to be part of version 0.4.2.
Severity
2.9 (Low)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-05-15 18:33 UTC
CWE
  • CWE-691 - Insufficient Control Flow Management
Assigner
References
Impacted products
Vendor Product Version
vyperlang vyper Affected: <= 0.4.2rc1
Create a notification for this product.
Show details on NVD website
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