CVE-2021-32681: Wagtail Cross-Site Scripting Vulnerability

MODERATE
Advisory Identifier: GHSA-xfrw-hxr5-ghqf
CVSS 5.4
CWE-79
Published
Advisory Summary

CVE-2021-32681 is a MODERATE (CVSS 5.4) cross-site scripting vulnerability (CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')) affecting Wagtail libraries in the PyPI ecosystem. The issue involves cross-site scripting in wagtail. Remediation is available by upgrading affected packages to version 2.11.8, 2.12.5, 2.13.2.

CVE-2021-32681 at a Glance

CVE Identifier CVE-2021-32681
GHSA Identifier GHSA-xfrw-hxr5-ghqf
Severity MODERATE
CVSS v3.1 Base Score 5.4
CWE Classification CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Affected Product Wagtail
Package Ecosystem PyPI
Published Date
Last Updated

Security Impact

CVSS: 5.4

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required Low (PR:L)
User Interaction Required (UI:R)
Scope Changed (S:C)
Confidentiality Low (C:L)
Integrity Low (I:L)
Availability None (A:N)

How to Fix CVE-2021-32681

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

wagtail fixed: 2.11.8
pip install wagtail>=2.11.8
wagtail fixed: 2.12.5
pip install wagtail>=2.12.5
wagtail fixed: 2.13.2
pip install wagtail>=2.13.2
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 wagtail

How to Check if You Are Affected

To determine whether your Python environment is affected by CVE-2021-32681, inspect your installed packages using pip:

pip show wagtail

Analyze the terminal output to locate any version of Wagtail in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 2.11.8), your application is affected.

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

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting'), where the product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. In Wagtail, 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

### Impact When the `{% include_block %}` template tag is used to output the value of a plain-text StreamField block (`CharBlock`, `TextBlock` or a similar user-defined block derived from `FieldBlock`), and that block does not specify a template for rendering, the tag output is not properly escaped as HTML. This could allow users to insert arbitrary HTML or scripting. This vulnerability is only exploitable by users with the ability to author StreamField content (i.e. users with 'editor' access to the Wagtail admin). ### Patches Patched versions have been released as Wagtail 2.11.8 (for the LTS 2.11 branch), Wagtail 2.12.5, and Wagtail 2.13.2 (for the current 2.13 branch). Site implementors who wish to retain the existing behaviour of allowing editors to insert HTML content in these blocks (and are willing to accept the risk of untrusted editors inserting arbitrary code) may disable the escaping by surrounding the relevant `{% include_block %}` tag in `{% autoescape off %}...{% endautoescape %}`. ### Workarounds Site implementors who are unable to upgrade to a current supported version should audit their use of `{% include_block %}` to ensure it is not used to output `CharBlock` / `TextBlock` values with no associated template. Note that this only applies where `{% include_block %}` is used directly on that block (uses of `include_block` on a block _containing_ a CharBlock / TextBlock, such as a StructBlock, are unaffected). In these cases, the tag can be replaced with Django's `{{ ... }}` syntax - e.g. `{% include_block my_title_block %}` becomes `{{ my_title_block }}`. ### Acknowledgements Many thanks to Karen Tracey for reporting this issue. ### For more information If you have any questions or comments about this advisory: * Visit Wagtail's [support channels](https://docs.wagtail.io/en/stable/support.html) * Email us at security@wagtail.io (if you wish to send encrypted email, the public key ID is `0x6ba1e1a86e0f8ce8`)

CVE-2021-32681 Affected Wagtail Versions

3 component(s)
Fixed Versions:
2.11.82.12.52.13.2
Product / Package Ecosystem Affected Versions Fixed Version
wagtail
PyPI
< 2.11.8
2.11.8
wagtail
PyPI
≥ 2.12
< 2.12.5
2.12.5
wagtail
PyPI
≥ 2.13
< 2.13.2
2.13.2

References

Frequently Asked Questions

What is CVE-2021-32681?
CVE-2021-32681 is a security vulnerability in Wagtail involving Cross-site Scripting in wagtail under CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting').
Which Wagtail versions are affected?
Affected versions include releases prior to 2.11.8, 2.12.5, 2.13.2 across affected packages: wagtail.
What version fixes CVE-2021-32681?
Upgrading to 2.11.8, 2.12.5, 2.13.2 (or the latest patched release for your respective branch) resolves the vulnerability.
Is wagtail affected?
Yes, wagtail is affected in releases prior to 2.11.8, 2.12.5, 2.13.2. Upgrade your dependency to 2.11.8, 2.12.5, 2.13.2 or later.
What is the CVSS score of CVE-2021-32681?
CVE-2021-32681 has a CVSS v3.1 base score of 5.4 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N.
What CWE is associated with CVE-2021-32681?
CVE-2021-32681 is classified under CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') (The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.).
How can I check PyPI dependencies for CVE-2021-32681?
Run the dependency tree command: 'pip show wagtail'. 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
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  "id" : "GHSA-xfrw-hxr5-ghqf",
  "modified" : "2026-06-09T13:02:48Z",
  "published" : "2021-06-17T20:10:42Z",
  "aliases" : [ "CVE-2021-32681" ],
  "summary" : "Cross-site Scripting in wagtail",
  "details" : "### Impact\nWhen the `{% include_block %}` template tag is used to output the value of a plain-text StreamField block (`CharBlock`, `TextBlock` or a similar user-defined block derived from `FieldBlock`), and that block does not specify a template for rendering, the tag output is not properly escaped as HTML. This could allow users to insert arbitrary HTML or scripting. This vulnerability is only exploitable by users with the ability to author StreamField content (i.e. users with 'editor' access to the Wagtail admin).\n\n### Patches\nPatched versions have been released as Wagtail 2.11.8 (for the LTS 2.11 branch), Wagtail 2.12.5, and Wagtail 2.13.2 (for the current 2.13 branch).\n\nSite implementors who wish to retain the existing behaviour of allowing editors to insert HTML content in these blocks (and are willing to accept the risk of untrusted editors inserting arbitrary code) may disable the escaping by surrounding the relevant `{% include_block %}` tag in `{% autoescape off %}...{% endautoescape %}`.\n\n### Workarounds\nSite implementors who are unable to upgrade to a current supported version should audit their use of `{% include_block %}` to ensure it is not used to output `CharBlock` / `TextBlock` values with no associated template. Note that this only applies where `{% include_block %}` is used directly on that block (uses of `include_block` on a block _containing_ a CharBlock / TextBlock, such as a StructBlock, are unaffected). In these cases, the tag can be replaced with Django's `{{ ... }}` syntax - e.g. `{% include_block my_title_block %}` becomes `{{ my_title_block }}`.\n\n### Acknowledgements\nMany thanks to Karen Tracey for reporting this issue.\n\n### For more information\nIf you have any questions or comments about this advisory:\n\n* Visit Wagtail's [support channels](https://docs.wagtail.io/en/stable/support.html)\n* Email us at security@wagtail.io (if you wish to send encrypted email, the public key ID is `0x6ba1e1a86e0f8ce8`)",
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}