CVE-2026-41255: Ckan CKAN Has CSRF Exemption Primed Vulnerability

MODERATE
Advisory Identifier: GHSA-mcvf-jxcw-vj73
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CVSS 6.1
CWE-352
Published
Advisory Summary

CVE-2026-41255 is a MODERATE (CVSS 6.1) ckan has csrf exemption primed vulnerability (CWE-352: Cross-Site Request Forgery (CSRF)) affecting Ckan libraries in the PyPI ecosystem. The issue involves ckan has csrf exemption primed by anonymous requests. Remediation is available by upgrading affected packages to version 2.10.10, 2.11.5.

CVE-2026-41255 at a Glance

CVE Identifier CVE-2026-41255
GHSA Identifier GHSA-mcvf-jxcw-vj73
Severity MODERATE
CVSS v3.1 Base Score 6.1
CWE Classification CWE-352: Cross-Site Request Forgery (CSRF)
Affected Product Ckan
Package Ecosystem PyPI
Published Date
Last Updated

Security Impact

CVSS: 6.1

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:R/S:C/C:L/I:L/A:N).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
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-2026-41255

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

ckan fixed: 2.10.10 
pip install ckan>=2.10.10
ckan fixed: 2.11.5 
pip install ckan>=2.11.5
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 ckan

How to Check if You Are Affected

To determine whether your Python environment is affected by CVE-2026-41255, inspect your installed packages using pip:

pip show ckan

Analyze the terminal output to locate any version of Ckan in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 2.10.10), your application is affected.

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

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-352: Cross-Site Request Forgery (CSRF), where the web application does not, or cannot, sufficiently verify whether a request was intentionally provided by the user who sent the request, which could have originated from an unauthorized actor. In Ckan, 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

Views can be marked as exempt from CSRF protection Access to the views via tokens or unauthenticated requests marked the endpoint as not requiring CSRF protection. The marking was a member variable in flask-wtf.csrf.CSRFProtect(), which was stored as a module level variable in the flask_app middleware. Thsi API was never intended for request level changes, it is primarily a decorator for static configuration. An unauthenticated request could hit a protected endpoint, exempting it from CSRF protection for the life of the particular server process. (e.g. one worker of uwsgi). This could be leveraged with XSS to perform actions using other user's credentials. ### References * [Vulnerability report](https://github.com/Shirshaw64p/security-advisories/tree/main/CVE-2026-41255) by @Shirshaw64p (original reporter)

CVE-2026-41255 Affected Ckan Versions

2 component(s)
Fixed Versions:
2.10.102.11.5
Product / Package Ecosystem Affected Versions Fixed Version
ckan
pypi/ckan
PyPI
≥ 2.10.0
< 2.10.10
2.10.10
ckan
pypi/ckan
PyPI
≥ 2.11.0
< 2.11.5
2.11.5

References

GitHub Advisory / Wiki ADVISORY
https://github.com/ckan/ckan/security/advisories/GHSA-mcvf-jxcw-vj73
NVD — CVE-2026-41255 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-41255
Ckan Security Information SECURITY
https://docs.ckan.org/en/2.10/changelog.html#v-2-10-10-2026-04-29
Ckan Security Information SECURITY
https://docs.ckan.org/en/2.11/changelog.html#v-2-11-5-2026-04-29
Ckan Source Repository REPOSITORY
https://github.com/Shirshaw64p/security-advisories/tree/main/CVE-2026-41255
Ckan Source Repository REPOSITORY
https://github.com/ckan/ckan

Frequently Asked Questions

What is CVE-2026-41255?
CVE-2026-41255 is a security vulnerability in Ckan involving CKAN has CSRF exemption primed by anonymous requests under CWE-352: Cross-Site Request Forgery (CSRF).
Which Ckan versions are affected?
Affected versions include releases prior to 2.10.10, 2.11.5 across affected packages: ckan.
What version fixes CVE-2026-41255?
Upgrading to 2.10.10, 2.11.5 (or the latest patched release for your respective branch) resolves the vulnerability.
Is ckan affected?
Yes, ckan is affected in releases prior to 2.10.10, 2.11.5. Upgrade your dependency to 2.10.10, 2.11.5 or later.
What is the CVSS score of CVE-2026-41255?
CVE-2026-41255 has a CVSS v3.1 base score of 6.1 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.
What CWE is associated with CVE-2026-41255?
CVE-2026-41255 is classified under CWE-352: Cross-Site Request Forgery (CSRF) (The web application does not, or cannot, sufficiently verify whether a request was intentionally provided by the user who sent the request, which could have originated from an unauthorized actor.).
How can I check PyPI dependencies for CVE-2026-41255?
Run the dependency tree command: 'pip show ckan'. 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-mcvf-jxcw-vj73",
  "modified" : "2026-05-14T20:39:41Z",
  "published" : "2026-04-29T20:36:07Z",
  "aliases" : [ "CVE-2026-41255" ],
  "summary" : "CKAN has CSRF exemption primed by anonymous requests",
  "details" : "Views can be marked as exempt from CSRF protection \n\nAccess to the views via tokens or unauthenticated requests marked the endpoint as not requiring CSRF protection. \n\nThe marking was a member variable in flask-wtf.csrf.CSRFProtect(), which was stored as a module level variable in the flask_app middleware. Thsi API was never intended for request level changes, it is primarily a decorator for static configuration. \n\nAn unauthenticated request could hit a protected endpoint, exempting it from CSRF protection for the life of the particular server process. (e.g. one worker of uwsgi).\n\nThis could be leveraged with XSS to perform actions using other user's credentials.\n\n### References\n\n* [Vulnerability report](https://github.com/Shirshaw64p/security-advisories/tree/main/CVE-2026-41255) by @Shirshaw64p (original reporter)",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "ckan"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "2.10.0"
      }, {
        "fixed" : "2.10.10"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "ckan"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "2.11.0"
      }, {
        "fixed" : "2.11.5"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 2.11.4"
    }
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/ckan/ckan/security/advisories/GHSA-mcvf-jxcw-vj73"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-41255"
  }, {
    "type" : "WEB",
    "url" : "https://docs.ckan.org/en/2.10/changelog.html#v-2-10-10-2026-04-29"
  }, {
    "type" : "WEB",
    "url" : "https://docs.ckan.org/en/2.11/changelog.html#v-2-11-5-2026-04-29"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/Shirshaw64p/security-advisories/tree/main/CVE-2026-41255"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/ckan/ckan"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-352" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-04-29T20:36:07Z",
    "nvd_published_at" : "2026-05-13T19:17:22Z"
  }
}