Summary
PyO3 Risk of buffer overflow in PyString::from_object
PyString::from_object took &str arguments and forwarded them directly to the Python C API without checking for terminating nul bytes. This could lead the Python interpreter to read beyond the end of the &str data and potentially leak contents of the out-of-bounds read (by raising a Python exception containing a copy of the data including the overflow).
In PyO3 0.24.1 this function will now allocate a CString to guarantee a terminating nul bytes. PyO3 0.25 will likely offer an alternative API which takes &CStr arguments.
Impact
A read operation accesses a memory location beyond the intended buffer boundary. Typical impact: sensitive data disclosure or crash.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
Already deployed Kodem?
See it in your environmentNew to Kodem? Get a demo →Remediation advice
Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.
Frequently Asked Questions
- What is GHSA-PPH8-GCV7-4QJ5? GHSA-PPH8-GCV7-4QJ5 is a low-severity out-of-bounds read vulnerability in pyo3 (rust), affecting versions >= 0.1.0, < 0.24.1. It is fixed in 0.24.1. A read operation accesses a memory location beyond the intended buffer boundary.
- Which versions of pyo3 are affected by GHSA-PPH8-GCV7-4QJ5? pyo3 (rust) versions >= 0.1.0, < 0.24.1 is affected.
- Is there a fix for GHSA-PPH8-GCV7-4QJ5? Yes. GHSA-PPH8-GCV7-4QJ5 is fixed in 0.24.1. Upgrade to this version or later.
- Is GHSA-PPH8-GCV7-4QJ5 exploitable, and should I be worried? Whether GHSA-PPH8-GCV7-4QJ5 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether GHSA-PPH8-GCV7-4QJ5 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix GHSA-PPH8-GCV7-4QJ5? Upgrade
pyo3to 0.24.1 or later.