Quick answers
- Is CVE-2025-26622 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2025-26622 being exploited in the wild.
- How severe is CVE-2025-26622?
- Medium severity, with a CVSS score of 4, published 21 February 2025.
- Which products and versions are affected?
- vyper (PyPI) ECOSYSTEM:introduced=0,fixed=0.4.1.
- Is there a fix for CVE-2025-26622?
- Yes. vyper (PyPI): upgrade to 0.4.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2025-26622 attacked?
- It is attacked over the network, in a software library.
- Am I affected by CVE-2025-26622?
- Check whether you run vyper (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
How to fix
- vyper (PyPI): upgrade to 0.4.1 or later
pip install "vyper>=0.4.1"
Technical details
Vyper's sqrt() builtin function implements the babylonian method to compute square roots of decimal numbers. The algorithm terminates when consecutive iterations are equal or after 256 iterations; however, for certain inputs, the result may oscillate between two values N and N+epsilon (where N² ≤ x < (N+epsilon)²), and the termination condition does not guarantee consistent rounding behavior. An attacker or deployed contract using sqrt() could encounter rounded-up results when rounded-down results are expected, affecting boundary conditions. The function diverges from the isqrt() integer variant, which consistently rounds down. The fix is tracked in pull request #4486 and patched in version 0.4.1.
Affected products
- Vyper Vyper <=0.4.0
Identifiers
- CVE-2025-26622
- GHSA-2p94-8669-xg86
- PYSEC-2025-29
Timeline
- 2025-02-21: disclosed
- 2025-02-21: patched: Fixed in version 0.4.1