Vulnerabilities in pkg:pypi/httpx

PACKAGE
Advisory Identifier: GHSA-h8pj-cxx2-jfg2
Share
Advisory Summary

CVE-2021-41945 is a CRITICAL (CVSS 9.1) improper input validation vulnerability (CWE-20: Improper Input Validation) affecting Httpx libraries in the PyPI ecosystem. The issue involves improper input validation in httpx. Remediation is available by upgrading affected packages to version 0.23.0.

1 Known Advisory Record(s)
Package Vulnerability Intelligence

pkg:pypi/httpx

1 Known Advisory Record(s)

Vulnerability advisories affecting package pkg:pypi/httpx. Select an advisory below to view technical details or fixes.

Advisory ID CVE / NVD Severity Summary
GHSA-h8pj-cxx2-jfg2 CVE-2021-41945 CRITICAL Improper Input Validation in httpx

CVE-2021-41945 at a Glance

CVE Identifier CVE-2021-41945
GHSA Identifier GHSA-h8pj-cxx2-jfg2
Severity CRITICAL
CVSS v3.1 Base Score 9.1
CWE Classification CWE-20: Improper Input Validation
Affected Product Httpx
Package Ecosystem PyPI
Published Date
Last Updated

Security Impact

CVSS: 9.1

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality High (C:H)
Integrity High (I:H)
Availability None (A:N)

How to Fix CVE-2021-41945

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

httpx fixed: 0.23.0 
pip install httpx>=0.23.0
Verify Direct and Transitive Dependencies

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

pip show httpx

How to Check if You Are Affected

To determine whether your Python environment is affected by CVE-2021-41945, inspect your installed packages using pip:

pip show httpx

Analyze the terminal output to locate any version of Httpx in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 0.23.0), your application is affected.

Note: The pip show httpx command checks currently installed packages in your active Python environment.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-20: Improper Input Validation, where the product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. In Httpx, 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

Encode OSS httpx <=1.0.0.beta0 is affected by improper input validation in `httpx.URL`, `httpx.Client` and some functions using `httpx.URL.copy_with`.

CVE-2021-41945 Affected Httpx Versions

1 component(s)
Fixed Versions:
0.23.0
Product / Package Ecosystem Affected Versions Fixed Version
httpx
pypi/httpx
PyPI
< 0.23.0
0.23.0

References

NVD — CVE-2021-41945 NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-41945
Httpx Source Repository REPOSITORY
https://github.com/encode/httpx/issues/2184
Httpx Source Repository REPOSITORY
https://github.com/encode/httpx/pull/2185
Httpx Source Repository REPOSITORY
https://github.com/encode/httpx/pull/2185/commits/e3c495a32c63d8aa7f1bcf3b7b27ee1a0ff428e1
Security Fix Commit FIX COMMIT
https://github.com/encode/httpx/commit/e9b0c85dd4f4e4469c57c4b38e5101fd12081b5c
Httpx Source Repository REPOSITORY
https://gist.github.com/lebr0nli/4edb76bbd3b5ff993cf44f2fbce5e571
GitHub Advisory / Wiki ADVISORY
https://github.com/advisories/GHSA-h8pj-cxx2-jfg2
Httpx Source Repository REPOSITORY
https://github.com/encode/httpx
Httpx Source Repository REPOSITORY
https://github.com/encode/httpx/discussions/1831
Httpx Release RELEASE
https://github.com/encode/httpx/releases/tag/0.23.0
Httpx Source Repository REPOSITORY
https://github.com/pypa/advisory-database/tree/main/vulns/httpx/PYSEC-2022-183.yaml
encode.com WEB
http://encode.com

Frequently Asked Questions

What is CVE-2021-41945?
CVE-2021-41945 is a security vulnerability in Httpx involving Improper Input Validation in httpx under CWE-20: Improper Input Validation.
Which Httpx versions are affected?
Affected versions include releases prior to 0.23.0 across affected packages: httpx.
What version fixes CVE-2021-41945?
Upgrading to 0.23.0 (or the latest patched release for your respective branch) resolves the vulnerability.
Is httpx affected?
Yes, httpx is affected in releases prior to 0.23.0. Upgrade your dependency to 0.23.0 or later.
What is the CVSS score of CVE-2021-41945?
CVE-2021-41945 has a CVSS v3.1 base score of 9.1 (CRITICAL) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N.
What CWE is associated with CVE-2021-41945?
CVE-2021-41945 is classified under CWE-20: Improper Input Validation (The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.).
How can I check PyPI dependencies for CVE-2021-41945?
Run the dependency tree command: 'pip show httpx'. 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-h8pj-cxx2-jfg2",
  "modified" : "2024-09-23T16:58:10Z",
  "published" : "2022-04-29T00:00:25Z",
  "aliases" : [ "CVE-2021-41945" ],
  "summary" : "Improper Input Validation in httpx",
  "details" : "Encode OSS httpx <=1.0.0.beta0 is affected by improper input validation in `httpx.URL`, `httpx.Client` and some functions using `httpx.URL.copy_with`.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N"
  }, {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "httpx"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "0.23.0"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2021-41945"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/encode/httpx/issues/2184"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/encode/httpx/pull/2185"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/encode/httpx/pull/2185/commits/e3c495a32c63d8aa7f1bcf3b7b27ee1a0ff428e1"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/encode/httpx/commit/e9b0c85dd4f4e4469c57c4b38e5101fd12081b5c"
  }, {
    "type" : "WEB",
    "url" : "https://gist.github.com/lebr0nli/4edb76bbd3b5ff993cf44f2fbce5e571"
  }, {
    "type" : "ADVISORY",
    "url" : "https://github.com/advisories/GHSA-h8pj-cxx2-jfg2"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/encode/httpx"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/encode/httpx/discussions/1831"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/encode/httpx/releases/tag/0.23.0"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/pypa/advisory-database/tree/main/vulns/httpx/PYSEC-2022-183.yaml"
  }, {
    "type" : "WEB",
    "url" : "http://encode.com"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-20" ],
    "severity" : "CRITICAL",
    "github_reviewed" : true,
    "github_reviewed_at" : "2022-04-29T22:55:38Z",
    "nvd_published_at" : "2022-04-28T14:15:00Z"
  }
}