CVE-2018-6596: Django anymail Django-Anymail Prone To A Timing Vulnerability

CRITICAL
Advisory Identifier: GHSA-hxf9-7h4c-f5jv
CVSS 9.1
CWE-200
Published
Advisory Summary

CVE-2018-6596 is a CRITICAL (CVSS 9.1) django-anymail prone to a timing vulnerability (CWE-200: Exposure of Sensitive Information to an Unauthorized Actor) affecting Django anymail libraries in the PyPI ecosystem. The issue involves django-anymail prone to a timing attack. Remediation is available by upgrading affected packages to version 1.2.1.

CVE-2018-6596 at a Glance

CVE Identifier CVE-2018-6596
GHSA Identifier GHSA-hxf9-7h4c-f5jv
Severity CRITICAL
CVSS v3.1 Base Score 9.1
CWE Classification CWE-200: Exposure of Sensitive Information to an Unauthorized Actor
Affected Product Django anymail
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:3.0/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-2018-6596

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

django-anymail fixed: 1.2.1
pip install django-anymail>=1.2.1
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 django-anymail

How to Check if You Are Affected

To determine whether your Python environment is affected by CVE-2018-6596, inspect your installed packages using pip:

pip show django-anymail

Analyze the terminal output to locate any version of Django anymail in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.2.1), your application is affected.

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

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-200: Exposure of Sensitive Information to an Unauthorized Actor, where the product exposes sensitive information to an actor that is not explicitly authorized to have access to that information. In Django anymail, 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

webhooks/base.py in Anymail (aka django-anymail) before 1.2.1 is prone to a timing attack vulnerability on the WEBHOOK_AUTHORIZATION secret, which allows remote attackers to post arbitrary e-mail tracking events.

CVE-2018-6596 Affected Django anymail Versions

1 component(s)
Fixed Versions:
1.2.1
Product / Package Ecosystem Affected Versions Fixed Version
django-anymail
PyPI
< 1.2.1
1.2.1

References

Frequently Asked Questions

What is CVE-2018-6596?
CVE-2018-6596 is a security vulnerability in Django anymail involving Django-Anymail prone to a timing attack under CWE-200: Exposure of Sensitive Information to an Unauthorized Actor.
Which Django anymail versions are affected?
Affected versions include releases prior to 1.2.1 across affected packages: django-anymail.
What version fixes CVE-2018-6596?
Upgrading to 1.2.1 (or the latest patched release for your respective branch) resolves the vulnerability.
Is django-anymail affected?
Yes, django-anymail is affected in releases prior to 1.2.1. Upgrade your dependency to 1.2.1 or later.
What is the CVSS score of CVE-2018-6596?
CVE-2018-6596 has a CVSS v3.1 base score of 9.1 (CRITICAL) with vector string CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N.
What CWE is associated with CVE-2018-6596?
CVE-2018-6596 is classified under CWE-200: Exposure of Sensitive Information to an Unauthorized Actor (The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.).
How can I check PyPI dependencies for CVE-2018-6596?
Run the dependency tree command: 'pip show django-anymail'. 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
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-hxf9-7h4c-f5jv",
  "modified" : "2024-09-16T21:24:24Z",
  "published" : "2018-07-12T20:30:40Z",
  "aliases" : [ "CVE-2018-6596" ],
  "summary" : "Django-Anymail prone to a timing attack",
  "details" : "webhooks/base.py in Anymail (aka django-anymail) before 1.2.1 is prone to a timing attack vulnerability on the WEBHOOK_AUTHORIZATION secret, which allows remote attackers to post arbitrary e-mail tracking events.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.0/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" : "django-anymail"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "1.2.1"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2018-6596"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/anymail/django-anymail/commit/c07998304b4a31df4c61deddcb03d3607a04691b"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/anymail/django-anymail/commit/db586ede1fbb41dce21310ea28ae15a1cf1286c5"
  }, {
    "type" : "WEB",
    "url" : "https://bugs.debian.org/889450"
  }, {
    "type" : "ADVISORY",
    "url" : "https://github.com/advisories/GHSA-hxf9-7h4c-f5jv"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/anymail/django-anymail"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/anymail/django-anymail/releases/tag/v1.2.1"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/anymail/django-anymail/releases/tag/v1.3"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/pypa/advisory-database/tree/main/vulns/django-anymail/PYSEC-2018-7.yaml"
  }, {
    "type" : "WEB",
    "url" : "https://www.debian.org/security/2018/dsa-4107"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-200" ],
    "severity" : "CRITICAL",
    "github_reviewed" : true,
    "github_reviewed_at" : "2020-06-16T21:41:20Z",
    "nvd_published_at" : null
  }
}