Vulnerability Description
Vyper is a Pythonic Smart Contract Language for the EVM. When the Vyper Compiler uses the precompiles EcRecover (0x1) and Identity (0x4), the success flag of the call is not checked. As a consequence an attacker can provide a specific amount of gas to make these calls fail but let the overall execution continue. Then the execution result can be incorrect. Based on EVM's rules, after the failed precompile the remaining code has only 1/64 of the pre-call-gas left (as 63/64 were forwarded and spent). Hence, only fairly simple executions can follow the failed precompile calls. Therefore, we found no significantly impacted real-world contracts. None the less an advisory has been made out of an abundance of caution. This issue is fixed in 0.4.1.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Vyperlang | Vyper | < 0.4.1 |
Related Weaknesses (CWE)
References
- https://github.com/vyperlang/vyper/commit/7136eab0a254aa2ff7ddca41cc05f2ee1fa99c
- https://github.com/vyperlang/vyper/pull/4451
- https://github.com/vyperlang/vyper/security/advisories/GHSA-vgf2-gvx8-xwc3ExploitVendor Advisory
- https://github.com/vyperlang/vyper/security/advisories/GHSA-vgf2-gvx8-xwc3ExploitVendor Advisory
FAQ
What is CVE-2025-21607?
CVE-2025-21607 is a vulnerability with a CVSS score of 7.5 (HIGH). Vyper is a Pythonic Smart Contract Language for the EVM. When the Vyper Compiler uses the precompiles EcRecover (0x1) and Identity (0x4), the success flag of the call is not checked. As a consequence ...
How severe is CVE-2025-21607?
CVE-2025-21607 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2025-21607?
Check the references section above for vendor advisories and patch information. Affected products include: Vyperlang Vyper.