Vulnerabilities in pkg:pypi/Flask

PACKAGE
Advisory Identifier: GHSA-5wv5-4vpf-pj6m
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Advisory Summary

CVE-2019-1010083 is a HIGH (CVSS 7.5) denial of service vulnerability (CWE-400: Uncontrolled Resource Consumption) affecting Flask libraries in the PyPI ecosystem. The issue involves pallets project flask is vulnerable to denial of service via unexpected memory usage. Remediation is available by upgrading affected packages to version 1.0.

3 Known Advisory Record(s)
Package Vulnerability Intelligence

pkg:pypi/Flask

3 Known Advisory Record(s)

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

Advisory ID CVE / NVD Severity Summary
GHSA-5wv5-4vpf-pj6m CVE-2019-1010083 HIGH Pallets Project Flask is vulnerable to Denial of Service via Unexpected memory usage
GHSA-562c-5r94-xh97 CVE-2018-1000656 HIGH Flask is vulnerable to Denial of Service via incorrect encoding of JSON data
GHSA-m2qf-hxjv-5gpq CVE-2023-30861 HIGH Flask vulnerable to possible disclosure of permanent session cookie due to missing Vary: Cookie header

CVE-2019-1010083 at a Glance

CVE Identifier CVE-2019-1010083
GHSA Identifier GHSA-5wv5-4vpf-pj6m
Severity HIGH
CVSS v3.1 Base Score 7.5
CWE Classification CWE-400: Uncontrolled Resource Consumption
Affected Product Flask
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:N/A:H).

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 None (I:N)
Availability High (A:H)

How to Fix CVE-2019-1010083

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

Flask fixed: 1.0 
pip install Flask>=1.0
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 Flask

How to Check if You Are Affected

To determine whether your Python environment is affected by CVE-2019-1010083, inspect your installed packages using pip:

pip show Flask

Analyze the terminal output to locate any version of Flask in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.0), your application is affected.

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

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-400: Uncontrolled Resource Consumption, where the product does not properly control the allocation and maintenance of a limited resource. In Flask, 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

The Pallets Project Flask before 1.0 is affected by unexpected memory usage. The impact is denial of service. The attack vector is crafted encoded JSON data. The fixed version is 1. NOTE this may overlap CVE-2018-1000656.

CVE-2019-1010083 Affected Flask Versions

1 component(s)
Fixed Versions:
1.0
Product / Package Ecosystem Affected Versions Fixed Version
Flask
pypi/Flask
PyPI
< 1.0
1.0

References

NVD — CVE-2019-1010083 NVD
https://nvd.nist.gov/vuln/detail/CVE-2019-1010083
GitHub Advisory / Wiki ADVISORY
https://github.com/advisories/GHSA-5wv5-4vpf-pj6m
Flask Source Repository REPOSITORY
https://github.com/pallets/flask
Flask Source Repository REPOSITORY
https://github.com/pypa/advisory-database/tree/main/vulns/flask/PYSEC-2019-179.yaml
www.palletsprojects.com/blog/flask-1-0-rele... WEB
https://www.palletsprojects.com/blog/flask-1-0-released

Frequently Asked Questions

What is CVE-2019-1010083?
CVE-2019-1010083 is a security vulnerability in Flask involving Pallets Project Flask is vulnerable to Denial of Service via Unexpected memory usage under CWE-400: Uncontrolled Resource Consumption.
Which Flask versions are affected?
Affected versions include releases prior to 1.0 across affected packages: Flask.
What version fixes CVE-2019-1010083?
Upgrading to 1.0 (or the latest patched release for your respective branch) resolves the vulnerability.
Is Flask affected?
Yes, Flask is affected in releases prior to 1.0. Upgrade your dependency to 1.0 or later.
What is the CVSS score of CVE-2019-1010083?
CVE-2019-1010083 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:N/A:H.
What CWE is associated with CVE-2019-1010083?
CVE-2019-1010083 is classified under CWE-400: Uncontrolled Resource Consumption (The product does not properly control the allocation and maintenance of a limited resource.).
How can I check PyPI dependencies for CVE-2019-1010083?
Run the dependency tree command: 'pip show Flask'. 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-5wv5-4vpf-pj6m",
  "modified" : "2024-09-20T21:04:58Z",
  "published" : "2019-07-19T16:12:46Z",
  "aliases" : [ "CVE-2019-1010083" ],
  "summary" : "Pallets Project Flask is vulnerable to Denial of Service via Unexpected memory usage",
  "details" : "The Pallets Project Flask before 1.0 is affected by unexpected memory usage. The impact is denial of service. The attack vector is crafted encoded JSON data. The fixed version is 1. NOTE this may overlap CVE-2018-1000656.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
  }, {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "Flask"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "1.0"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2019-1010083"
  }, {
    "type" : "ADVISORY",
    "url" : "https://github.com/advisories/GHSA-5wv5-4vpf-pj6m"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/pallets/flask"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/pypa/advisory-database/tree/main/vulns/flask/PYSEC-2019-179.yaml"
  }, {
    "type" : "WEB",
    "url" : "https://www.palletsprojects.com/blog/flask-1-0-released"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-400" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2019-07-19T04:59:45Z",
    "nvd_published_at" : "2019-07-17T14:15:00Z"
  }
}