Vulnerabilities in pkg:pypi/Markdown

PACKAGE
Advisory Identifier: GHSA-5wmx-573v-2qwq
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Advisory Summary

CVE-2025-69534 is a MODERATE (CVSS 7.5) python-markdown has an uncaught exception vulnerability (CWE-400: Uncontrolled Resource Consumption) affecting Markdown libraries in the PyPI ecosystem. The issue involves python-markdown has an uncaught exception. Remediation is available by upgrading affected packages to version 3.8.1.

1 Known Advisory Record(s)
Package Vulnerability Intelligence

pkg:pypi/Markdown

1 Known Advisory Record(s)

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

Advisory ID CVE / NVD Severity Summary
GHSA-5wmx-573v-2qwq CVE-2025-69534 MODERATE Python-Markdown has an Uncaught Exception

CVE-2025-69534 at a Glance

CVE Identifier CVE-2025-69534
GHSA Identifier GHSA-5wmx-573v-2qwq
Severity MODERATE
CVSS v3.1 Base Score 7.5
CWE Classification CWE-400: Uncontrolled Resource Consumption
Affected Product Markdown
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-2025-69534

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

Markdown fixed: 3.8.1 
pip install Markdown>=3.8.1
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 Markdown

How to Check if You Are Affected

To determine whether your Python environment is affected by CVE-2025-69534, inspect your installed packages using pip:

pip show Markdown

Analyze the terminal output to locate any version of Markdown in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 3.8.1), your application is affected.

Note: The pip show Markdown 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 Markdown, 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

Python-Markdown version 3.8 contain a vulnerability where malformed HTML-like sequences can cause html.parser.HTMLParser to raise an unhandled AssertionError during Markdown parsing. Because Python-Markdown does not catch this exception, any application that processes attacker-controlled Markdown may crash. This enables remote, unauthenticated Denial of Service in web applications, documentation systems, CI/CD pipelines, and any service that renders untrusted Markdown. The issue was acknowledged by the vendor and fixed in version 3.8.1. This issue causes a remote Denial of Service in any application parsing untrusted Markdown, and can lead to Information Disclosure through uncaught exceptions.

CVE-2025-69534 Affected Markdown Versions

1 component(s)
Fixed Versions:
3.8.1
Product / Package Ecosystem Affected Versions Fixed Version
Markdown
pypi/Markdown
PyPI
< 3.8.1
3.8.1

References

NVD — CVE-2025-69534 NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-69534
Markdown Source Repository REPOSITORY
https://github.com/Python-Markdown/markdown/issues/1534
Markdown Source Repository REPOSITORY
https://github.com/Python-Markdown/markdown/pull/1535
Markdown Source Repository REPOSITORY
https://github.com/Python-Markdown/markdown
Markdown Source Repository REPOSITORY
https://github.com/Python-Markdown/markdown/actions/runs/15736122892
Markdown Source Repository REPOSITORY
https://github.com/pypa/advisory-database/tree/main/vulns/markdown/PYSEC-2026-89.yaml
Markdown Security Information SECURITY
http://www.openwall.com/lists/oss-security/2026/03/06/4

Frequently Asked Questions

What is CVE-2025-69534?
CVE-2025-69534 is a security vulnerability in Markdown involving Python-Markdown has an Uncaught Exception under CWE-400: Uncontrolled Resource Consumption.
Which Markdown versions are affected?
Affected versions include releases prior to 3.8.1 across affected packages: Markdown.
What version fixes CVE-2025-69534?
Upgrading to 3.8.1 (or the latest patched release for your respective branch) resolves the vulnerability.
Is Markdown affected?
Yes, Markdown is affected in releases prior to 3.8.1. Upgrade your dependency to 3.8.1 or later.
What is the CVSS score of CVE-2025-69534?
CVE-2025-69534 has a CVSS v3.1 base score of 7.5 (MODERATE) 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-2025-69534?
CVE-2025-69534 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-2025-69534?
Run the dependency tree command: 'pip show Markdown'. 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-5wmx-573v-2qwq",
  "modified" : "2026-06-06T00:53:00Z",
  "published" : "2026-03-05T15:30:36Z",
  "aliases" : [ "CVE-2025-69534" ],
  "summary" : "Python-Markdown has an Uncaught Exception",
  "details" : "Python-Markdown version 3.8 contain a vulnerability where malformed HTML-like sequences can cause html.parser.HTMLParser to raise an unhandled AssertionError during Markdown parsing. Because Python-Markdown does not catch this exception, any application that processes attacker-controlled Markdown may crash. This enables remote, unauthenticated Denial of Service in web applications, documentation systems, CI/CD pipelines, and any service that renders untrusted Markdown. The issue was acknowledged by the vendor and fixed in version 3.8.1. This issue causes a remote Denial of Service in any application parsing untrusted Markdown, and can lead to Information Disclosure through uncaught exceptions.",
  "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:L/SC:N/SI:N/SA:N/E:P"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "Markdown"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "3.8.1"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2025-69534"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/Python-Markdown/markdown/issues/1534"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/Python-Markdown/markdown/pull/1535"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/Python-Markdown/markdown"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/Python-Markdown/markdown/actions/runs/15736122892"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/pypa/advisory-database/tree/main/vulns/markdown/PYSEC-2026-89.yaml"
  }, {
    "type" : "WEB",
    "url" : "http://www.openwall.com/lists/oss-security/2026/03/06/4"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-248", "CWE-400" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-03-05T21:59:47Z",
    "nvd_published_at" : "2026-03-05T15:16:11Z"
  }
}