CVE-2025-69534
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Last Modified:
Description
A flaw was found in Python-Markdown. Parsing crafted markdown content containing malformed HTML-like sequences causes html.parser.HTMLParser to raise an unhandled AssertionError. This unhandled exception allows an attacker to cause an application crash and potentially disclose sensitive information via its stack trace.
Statement
To exploit this flaw, an attacker must be able to supply a specially crafted payload to be processed by an application using Python-Markdown. Additionally, the security impact of this vulnerability is limited to an information disclosure via the unhandled exception stack trace and a denial of service. There is no memory corruption or arbitrary command execution. Due to these reasons, this issue has been rated with an important severity.
Mitigation
To mitigate this vulnerability, wrap your markdown parsing function in a try/except block. This catches the unhandled exception, preventing both the application crash and the stack trace leak.
Additional Information
- This content is not included.Bugzilla 2444839: python-markdown: denial of service via malformed HTML-like sequences
- Content from cwe.mitre.org is not included.CWE-617: Reachable Assertion
- FAQ: Frequently asked questions about CVE-2025-69534
- Offline Security Data data is available for integration with other systems. See Offline Security Data API to get started.
External References
Content from www.cve.org is not included.https://www.cve.org/CVERecord?id=CVE-2025-69534
Content from nvd.nist.gov is not included.https://nvd.nist.gov/vuln/detail/CVE-2025-69534
Content from github.com is not included.https://github.com/Python-Markdown/markdown
Content from github.com is not included.https://github.com/Python-Markdown/markdown/issues/1534
Affected Packages and Issued Red Hat Security Errata
| Products / Services | Components | State | Errata |
|---|---|---|---|
| External Secrets Operator for Red Hat OpenShift | external-secrets-operator/bitwarden-sdk-server-rhel9 | Not affected | |
| External Secrets Operator for Red Hat OpenShift | external-secrets-operator/external-secrets-operator-bundle | Not affected | |
| External Secrets Operator for Red Hat OpenShift | external-secrets-operator/external-secrets-operator-rhel9 | Not affected | |
| External Secrets Operator for Red Hat OpenShift | external-secrets-operator/external-secrets-rhel9 | Not affected | |
| Multicluster Engine for Kubernetes | multicluster-engine/assisted-installer-agent-rhel9 | Not affected | |
| Multicluster Engine for Kubernetes | multicluster-engine/assisted-installer-controller-rhel9 | Not affected | |
| Multicluster Engine for Kubernetes | multicluster-engine/assisted-installer-rhel9 | Not affected | |
| Multicluster Engine for Kubernetes | multicluster-engine/assisted-service-8-rhel8 | Not affected | |
| Multicluster Engine for Kubernetes | multicluster-engine/assisted-service-9-rhel9 | Not affected | |
| Red Hat Ansible Automation Platform 2 | ansible-automation-platform-26/controller-rhel9 | Affected | |
| Red Hat Ansible Automation Platform 2 | ansible-automation-platform-26/hub-rhel9 | Not affected | |
| Red Hat Ansible Automation Platform 2 | python-markdown | Not affected | |
| Red Hat Ansible Automation Platform 2.5 for RHEL 8 | python3.12-markdown | Fixed | RHSA-2026:13512 |
| Red Hat Ansible Automation Platform 2.5 for RHEL 9 | python3.12-markdown | Fixed | RHSA-2026:13512 |
| Red Hat Ansible Automation Platform 2.6 for RHEL 9 | automation-controller | Fixed | RHSA-2026:13508 |
| Red Hat Ansible Automation Platform 2.6 for RHEL 9 | python3.12-markdown | Fixed | RHSA-2026:13508 |
| Red Hat Developer Hub 1.8 | rhdh/rhdh-hub-rhel9 | Fixed | RHSA-2026:9742 |
| Red Hat Developer Hub 1.9 | rhdh/rhdh-hub-rhel9 | Fixed | RHSA-2026:13826 |
| Red Hat Enterprise Linux 10 | python-markdown | Fixed | This content is not included.RHSA-2026:19155 |
| Red Hat Enterprise Linux 10.0 Extended Update Support | python-markdown | Fixed | RHSA-2026:20677 |
| Red Hat Enterprise Linux 6 | python-markdown | Not affected | |
| Red Hat Enterprise Linux 8 | python-markdown | Not affected | |
| Red Hat Enterprise Linux 9 | python-markdown | Fixed | RHSA-2026:19366 |
| Red Hat Enterprise Linux 9.4 Extended Update Support | python-markdown | Fixed | This content is not included.RHSA-2026:20674 |
| Red Hat Enterprise Linux 9.6 Extended Update Support | python-markdown | Fixed | This content is not included.RHSA-2026:20676 |
| Red Hat OpenShift AI (RHOAI) | rhoai/odh-modelmesh-runtime-adapter-rhel8 | Affected | |
| Red Hat OpenShift AI (RHOAI) | rhoai/odh-built-in-detector-rhel9 | Not affected | |
| Red Hat OpenShift AI (RHOAI) | rhoai/odh-guardrails-detector-huggingface-runtime-rhel9 | Not affected | |
| Red Hat OpenShift AI (RHOAI) | rhoai/odh-kserve-agent-rhel9 | Not affected | |
| Red Hat OpenShift AI (RHOAI) | rhoai/odh-kserve-controller-rhel9 | Not affected | |
| Red Hat OpenShift AI (RHOAI) | rhoai/odh-kserve-router-rhel9 | Not affected | |
| Red Hat OpenShift AI (RHOAI) | rhoai/odh-pipeline-runtime-pytorch-cuda-py312-rhel9 | Not affected | |
| Red Hat OpenShift AI (RHOAI) | rhoai/odh-pipeline-runtime-pytorch-llmcompressor-cuda-py312-rhel9 | Not affected | |
| Red Hat OpenShift AI (RHOAI) | rhoai/odh-pipeline-runtime-pytorch-rocm-py312-rhel9 | Not affected | |
| Red Hat OpenShift AI (RHOAI) | rhoai/odh-pipeline-runtime-tensorflow-cuda-py312-rhel9 | Not affected | |
| Red Hat OpenShift AI (RHOAI) | rhoai/odh-pipeline-runtime-tensorflow-rocm-py312-rhel9 | Not affected | |
| Red Hat OpenShift AI (RHOAI) | rhoai/odh-training-cuda128-torch28-py312-rhel9 | Not affected | |
| Red Hat OpenShift AI (RHOAI) | rhoai/odh-training-rocm64-torch28-py312-rhel9 | Not affected | |
| Red Hat OpenShift AI (RHOAI) | rhoai/odh-vllm-gaudi-rhel9 | Not affected | |
| Red Hat OpenShift AI (RHOAI) | rhoai/odh-workbench-jupyter-pytorch-cuda-py312-rhel9 | Not affected | |
| Red Hat OpenShift AI (RHOAI) | rhoai/odh-workbench-jupyter-pytorch-llmcompressor-cuda-py312-rhel9 | Not affected | |
| Red Hat OpenShift AI (RHOAI) | rhoai/odh-workbench-jupyter-pytorch-rocm-py312-rhel9 | Not affected | |
| Red Hat OpenShift AI (RHOAI) | rhoai/odh-workbench-jupyter-tensorflow-cuda-py312-rhel9 | Not affected | |
| Red Hat OpenShift AI (RHOAI) | rhoai/odh-workbench-jupyter-tensorflow-rocm-py312-rhel9 | Not affected | |
| Red Hat OpenShift AI (RHOAI) | rhoai/odh-training-cuda121-torch24-py311-rhel9 | Will not fix | |
| Red Hat OpenShift AI (RHOAI) | rhoai/odh-training-rocm62-torch24-py311-rhel9 | Will not fix | |
| Red Hat OpenShift AI 2.25 | rhoai/odh-modelmesh-runtime-adapter-rhel9 | Fixed | RHSA-2026:10184 |
| Red Hat OpenShift AI 2.25 | rhoai/odh-training-cuda124-torch25-py311-rhel9 | Fixed | RHSA-2026:10184 |
| Red Hat OpenShift AI 2.25 | rhoai/odh-training-rocm62-torch25-py311-rhel9 | Fixed | RHSA-2026:10184 |
| Red Hat OpenShift Container Platform 4 | openshift4/ose-olm-catalogd-rhel9 | Affected | |
| Red Hat OpenShift Container Platform 4 | openshift4/ose-agent-installer-api-server-rhel9 | Not affected | |
| Red Hat OpenShift Dev Spaces | devspaces/traefik-rhel9 | Not affected | |
| Red Hat Satellite 6 | satellite:el8/python-markdown | Affected | |
| Red Hat Satellite 6 | satellite/iop-advisor-backend-rhel9 | Not affected | |
| Red Hat Satellite 6.16 for RHEL 8 | python-markdown | Fixed | RHSA-2026:14874 |
| Red Hat Satellite 6.16 for RHEL 9 | python-markdown | Fixed | RHSA-2026:14874 |
| Red Hat Satellite 6.17 for RHEL 9 | python-markdown | Fixed | RHSA-2026:14873 |
| Red Hat Satellite 6.18 for RHEL 9 | python3.12-markdown | Fixed | RHSA-2026:14835 |
Common Vulnerability Scoring System (CVSS) Score Details
Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authorities (CNA) source for its products and services (see Red Hat classifications ).
| CVSS v3 Score Breakdown | Red Hat | NVD |
|---|---|---|
| CVSS v3 Base Score | 8.2 | 7.5 |
| Attack Vector | Network | Network |
| Attack Complexity | Low | Low |
| Privileges Required | None | None |
| User Interaction | None | None |
| Scope | Unchanged | Unchanged |
| Confidentiality Impact | Low | None |
| Integrity Impact | None | None |
| Availability Impact | High | High |
CVSS v3 Vector
Red Hat CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H
NVD CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Red Hat CVSS v3 Score Explanation
This flaw allows an attacker to obtain sensitive information via the stack trace of the unhandled exception, such as file paths and library versions. However, an attacker does not have full control of what information is obtained. To reflect this condition, the confidentiality metric is set to low.
Frequently Asked Questions
Why is Red Hat's CVSS v3 score or Impact different from other vendors?
For more information, see https://access.redhat.com/solutions/762393.
My product is listed as "Under investigation" or "Affected", when will Red Hat release a fix for this vulnerability?
- "Under investigation" doesn't necessarily mean that the product is affected by this vulnerability. It only means that our Analysis Team is still working on determining whether the product is affected and how it is affected.
- "Affected" means that our Analysis Team has determined that this product is affected by this vulnerability and might release a fix to address this in the near future.
What can I do if my product is listed as "Will not fix"?
Available options depend mostly on the Impact of the vulnerability and the current Life Cycle phase of your product. Overall, you have the following options:
- Upgrade to a supported product version that includes a fix for this vulnerability (recommended).
- Apply a mitigation (if one exists).
- Open a This content is not included.support case to request a prioritization of releasing a fix for this vulnerability.
What can I do if my product is listed as "Fix deferred"?
Available options depend mostly on the Impact of the vulnerability and the current Life Cycle phase of your product. Overall, you have the following options:
- Apply a mitigation (if one exists).
- Open a This content is not included.support case to request a prioritization of releasing a fix for this vulnerability.
- Red Hat Engineering focuses on addressing high-priority issues based on their complexity or limited lifecycle support. Therefore, lower-priority issues will not receive immediate fixes.
What is a mitigation?
I have a Red Hat product but it is not in the above list, is it affected?
Why is my security scanner reporting my product as vulnerable to this vulnerability even though my product version is fixed or not affected?
My product is listed as "Out of Support Scope". What does this mean?
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