CVE-2024-32649 vyper performs double eval of the argument of sqrt

What is CVE-2024-32649?

CVE-2024-32649 is a medium-severity code injection vulnerability in vyperlang vyper, published on 25 Apr 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

Vyper is a pythonic Smart Contract Language for the Ethereum virtual machine. In versions 0.3.10 and prior, using the `sqrt` builtin can result in double eval vulnerability when the argument has side-effects. It can be seen that the `build_IR` function of the `sqrt` builtin doesn't cache the argument to the stack. As such, it can be evaluated multiple times (instead of retrieving the value from the stack). No vulnerable production contracts were found. Additionally, double evaluation of side-effects should be easily discoverable in client tests. As such, the impact is low. As of time of publication, no fixed versions are available.

Weakness: CWE-95

Which versions are affected by CVE-2024-32649?

3 open source packages ship an affected version, including vyper. It affects 1 product.

Products include Vyperlang Vyper.

How do I fix CVE-2024-32649?

Upgrade vyper to 0.4.0 or later.

Upgrade, and never evaluate templates, expressions or code built from user input. More about Code injection.

Is CVE-2024-32649 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2024-32649 exists.

Other vulnerabilities in vyperlang vyper

• CVE-2024-24563 Vyper array negative index vulnerability Critical 9.8
• CVE-2024-24561 Vyper bounds check on built-in `slice()` function can be overflowed Critical 9.8
• CVE-2023-39363 Vyper incorrectly allocated named re-entrancy locks Critical 9.1
• CVE-2022-24845 Integer bounds error in Vyper High 8.8
• CVE-2022-29255 Multiple evaluation of contract address in call in vyper High 8.2

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-5jrj-52x8-m64h, PYSEC-2024-209.