GHSA-pph8-gcv7-4qj5: Pyo3 :from_object` Vulnerability

LOW
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CWE-125
Published
Advisory Summary

GHSA-pph8-gcv7-4qj5 is a LOW :from_object` vulnerability (CWE-125: Out-of-bounds Read) affecting Pyo3 libraries in the crates.io ecosystem. The issue involves :from_object`. Remediation is available by upgrading affected packages to version 0.24.1.

GHSA-pph8-gcv7-4qj5 at a Glance

CVE Identifier N/A
GHSA Identifier GHSA-pph8-gcv7-4qj5
Severity LOW
CVSS v3.1 Base Score N/A
CWE Classification CWE-125: Out-of-bounds Read
Affected Product Pyo3
Package Ecosystem crates.io
Published Date
Last Updated

How to Fix GHSA-pph8-gcv7-4qj5

To remediate this vulnerability, upgrade all affected Pyo3 dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

pyo3 fixed: 0.24.1 
Upgrade pyo3 to 0.24.1
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

inspect dependencies for pyo3

How to Check if You Are Affected

To determine whether your application is affected by GHSA-pph8-gcv7-4qj5, inspect your project dependencies for Pyo3:

inspect dependencies for pyo3

Analyze the terminal output to locate any version of Pyo3 in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 0.24.1), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-125: Out-of-bounds Read, where the product reads data past the end, or before the beginning, of the intended buffer. In Pyo3, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

`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.

GHSA-pph8-gcv7-4qj5 Affected Pyo3 Versions

1 component(s)
Fixed Versions:
0.24.1
Product / Package Ecosystem Affected Versions Fixed Version
pyo3
 crates.io
≥ 0.1.0
< 0.24.1
0.24.1

References

Pyo3 Source Repository REPOSITORY
https://github.com/PyO3/pyo3/issues/5005
Pyo3 Source Repository REPOSITORY
https://github.com/PyO3/pyo3/pull/5008
Pyo3 Source Repository REPOSITORY
https://github.com/PyO3/pyo3
rustsec.org/advisories/rustsec-... WEB
https://rustsec.org/advisories/RUSTSEC-2025-0020.html

Frequently Asked Questions

What is GHSA-pph8-gcv7-4qj5?
GHSA-pph8-gcv7-4qj5 is a security vulnerability in Pyo3 involving :from_object` under CWE-125: Out-of-bounds Read.
Which Pyo3 versions are affected?
Affected versions include releases prior to 0.24.1 across affected packages: pyo3.
What version fixes GHSA-pph8-gcv7-4qj5?
Upgrading to 0.24.1 (or the latest patched release for your respective branch) resolves the vulnerability.
Is pyo3 affected?
Yes, pyo3 is affected in releases prior to 0.24.1. Upgrade your dependency to 0.24.1 or later.
What CWE is associated with GHSA-pph8-gcv7-4qj5?
GHSA-pph8-gcv7-4qj5 is classified under CWE-125: Out-of-bounds Read (The product reads data past the end, or before the beginning, of the intended buffer.).
How can I check crates.io dependencies for GHSA-pph8-gcv7-4qj5?
Run the dependency tree command: 'inspect dependencies for pyo3'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-pph8-gcv7-4qj5",
  "modified" : "2025-04-02T13:19:19Z",
  "published" : "2025-04-02T13:19:19Z",
  "aliases" : [ ],
  "summary" : "PyO3 Risk of buffer overflow in `PyString::from_object`",
  "details" : "`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).\n\nIn 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.",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "crates.io",
      "name" : "pyo3"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0.1.0"
      }, {
        "fixed" : "0.24.1"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/PyO3/pyo3/issues/5005"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/PyO3/pyo3/pull/5008"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/PyO3/pyo3"
  }, {
    "type" : "WEB",
    "url" : "https://rustsec.org/advisories/RUSTSEC-2025-0020.html"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-125" ],
    "severity" : "LOW",
    "github_reviewed" : true,
    "github_reviewed_at" : "2025-04-02T13:19:19Z",
    "nvd_published_at" : null
  }
}