Vulnerabilities in pkg:pypi/proxy.py

PACKAGE
Advisory Identifier: GHSA-cmc7-mfmr-xqrx
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Advisory Summary

CVE-2021-3116 is a HIGH (CVSS 7.5) logic error vulnerability (CWE-287: Improper Authentication) affecting Proxy.py libraries in the PyPI ecosystem. The issue involves logic error in authentication in proxy.py. Remediation is available by upgrading affected packages to version 2.3.1.

1 Known Advisory Record(s)
Package Vulnerability Intelligence

pkg:pypi/proxy.py

1 Known Advisory Record(s)

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

Advisory ID CVE / NVD Severity Summary
GHSA-cmc7-mfmr-xqrx CVE-2021-3116 HIGH Logic error in authentication in proxy.py

CVE-2021-3116 at a Glance

CVE Identifier CVE-2021-3116
GHSA Identifier GHSA-cmc7-mfmr-xqrx
Severity HIGH
CVSS v3.1 Base Score 7.5
CWE Classification CWE-287: Improper Authentication
Affected Product Proxy.py
Package Ecosystem PyPI
Published Date
Last Updated

Security Impact

CVSS: 7.5

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:N/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 None (C:N)
Integrity High (I:H)
Availability None (A:N)

How to Fix CVE-2021-3116

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

proxy.py fixed: 2.3.1 
pip install proxy.py>=2.3.1
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 proxy.py

How to Check if You Are Affected

To determine whether your Python environment is affected by CVE-2021-3116, inspect your installed packages using pip:

pip show proxy.py

Analyze the terminal output to locate any version of Proxy.py in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 2.3.1), your application is affected.

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

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-287: Improper Authentication, where when an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. In Proxy.py, 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

before_upstream_connection in AuthPlugin in http/proxy/auth.py in proxy.py before 2.3.1 accepts incorrect Proxy-Authorization header data because of a boolean confusion (and versus or).

CVE-2021-3116 Affected Proxy.py Versions

1 component(s)
Fixed Versions:
2.3.1
Product / Package Ecosystem Affected Versions Fixed Version
proxy.py
pypi/proxy.py
PyPI
< 2.3.1
2.3.1

References

NVD — CVE-2021-3116 NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-3116
Proxy.py Source Repository REPOSITORY
https://github.com/abhinavsingh/proxy.py/pull/482
Proxy.py Source Repository REPOSITORY
https://github.com/abhinavsingh/proxy.py/pull/482/commits/9b00093288237f5073c403f2c4f62acfdfa8ed46
Security Fix Commit FIX COMMIT
https://github.com/abhinavsingh/proxy.py/commit/bff171ec26d826ae1d22d2466eaf9d8bdbf059d3
cardaci.xyz/advisories/2021/01/... WEB
https://cardaci.xyz/advisories/2021/01/10/proxy.py-2.3.0-broken-basic-authentication
Proxy.py Source Repository REPOSITORY
https://github.com/abhinavsingh/proxy.py
GitHub Advisory / Wiki ADVISORY
https://github.com/advisories/GHSA-cmc7-mfmr-xqrx
Proxy.py Source Repository REPOSITORY
https://github.com/pypa/advisory-database/tree/main/vulns/proxy-py/PYSEC-2021-46.yaml
pypi.org/project/proxy.py/2.... WEB
https://pypi.org/project/proxy.py/2.3.1/#history

Frequently Asked Questions

What is CVE-2021-3116?
CVE-2021-3116 is a security vulnerability in Proxy.py involving Logic error in authentication in proxy.py under CWE-287: Improper Authentication.
Which Proxy.py versions are affected?
Affected versions include releases prior to 2.3.1 across affected packages: proxy.py.
What version fixes CVE-2021-3116?
Upgrading to 2.3.1 (or the latest patched release for your respective branch) resolves the vulnerability.
Is proxy.py affected?
Yes, proxy.py is affected in releases prior to 2.3.1. Upgrade your dependency to 2.3.1 or later.
What is the CVSS score of CVE-2021-3116?
CVE-2021-3116 has a CVSS v3.1 base score of 7.5 (HIGH) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N.
What CWE is associated with CVE-2021-3116?
CVE-2021-3116 is classified under CWE-287: Improper Authentication (When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.).
How can I check PyPI dependencies for CVE-2021-3116?
Run the dependency tree command: 'pip show proxy.py'. 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-cmc7-mfmr-xqrx",
  "modified" : "2024-10-21T21:02:47Z",
  "published" : "2021-04-07T21:01:25Z",
  "aliases" : [ "CVE-2021-3116" ],
  "summary" : "Logic error in authentication in proxy.py",
  "details" : "before_upstream_connection in AuthPlugin in http/proxy/auth.py in proxy.py before 2.3.1 accepts incorrect Proxy-Authorization header data because of a boolean confusion (and versus or).",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N"
  }, {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "proxy.py"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "2.3.1"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2021-3116"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/abhinavsingh/proxy.py/pull/482"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/abhinavsingh/proxy.py/pull/482/commits/9b00093288237f5073c403f2c4f62acfdfa8ed46"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/abhinavsingh/proxy.py/commit/bff171ec26d826ae1d22d2466eaf9d8bdbf059d3"
  }, {
    "type" : "WEB",
    "url" : "https://cardaci.xyz/advisories/2021/01/10/proxy.py-2.3.0-broken-basic-authentication"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/abhinavsingh/proxy.py"
  }, {
    "type" : "ADVISORY",
    "url" : "https://github.com/advisories/GHSA-cmc7-mfmr-xqrx"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/pypa/advisory-database/tree/main/vulns/proxy-py/PYSEC-2021-46.yaml"
  }, {
    "type" : "WEB",
    "url" : "https://pypi.org/project/proxy.py/2.3.1/#history"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-287", "CWE-480", "CWE-697" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2021-04-06T21:58:49Z",
    "nvd_published_at" : "2021-01-11T05:15:00Z"
  }
}