CVE-2026-26274: October/october October CMS Has Safe Mode Vulnerability

MODERATE
Advisory Identifier: GHSA-h6jm-f4hh-fw27
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CVSS 6.6
CWE-863 CWE-184
Published
Advisory Summary

CVE-2026-26274 is a MODERATE (CVSS 6.6) october cms has safe mode vulnerability (CWE-863: Incorrect Authorization) affecting October/october libraries in the Packagist ecosystem. The issue involves october cms has safe mode bypass via twig database write operations. Remediation is available by upgrading affected packages to version 3.7.14, 4.1.10.

CVE-2026-26274 at a Glance

CVE Identifier CVE-2026-26274
GHSA Identifier GHSA-h6jm-f4hh-fw27
Severity MODERATE
CVSS v3.1 Base Score 6.6
CWE Classification CWE-863: Incorrect Authorization
Affected Product October/october
Package Ecosystem Packagist
Published Date
Last Updated

Security Impact

CVSS: 6.6

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

Attack Vector Network (AV:N)
Attack Complexity High (AC:H)
Privileges Required High (PR:H)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality High (C:H)
Integrity High (I:H)
Availability High (A:H)

How to Fix CVE-2026-26274

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

october/october fixed: 3.7.14 
Upgrade october/october to 3.7.14
october/october fixed: 4.1.10 
Upgrade october/october to 4.1.10
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

inspect dependencies for october/october

How to Check if You Are Affected

To determine whether your application is affected by CVE-2026-26274, inspect your project dependencies for October/october:

inspect dependencies for october/october

Analyze the terminal output to locate any version of October/october in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 3.7.14), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-863: Incorrect Authorization, where the product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check. In October/october, 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

A vulnerability was identified in the Twig sandbox security policy that allowed database write operations when `cms.safe_mode` is enabled. Backend users with Developer permissions could use Twig template markup to execute insert, update, and delete operations on any database table through the query builder, which is included in the sandbox allow-list. ### Impact - Arbitrary database writes including modification or deletion of any table - Requires authenticated backend access with Developer permissions - Only relevant when `cms.safe_mode` is enabled (otherwise direct PHP injection is already possible) ### Patches The vulnerability has been patched in v3.7.14 and v4.1.10. Write operations such as `insert`, `update`, `delete`, and `truncate` are now blocked on query builder and model objects within the Twig sandbox. All users are encouraged to upgrade to the latest patched version. ### Workarounds If upgrading immediately is not possible: - Restrict Developer tool access to fully trusted administrators only ### Reporter - Reported by [Chris Alupului](https://github.com/neosprings)

CVE-2026-26274 Affected October/october Versions

2 component(s)
Fixed Versions:
3.7.144.1.10
Product / Package Ecosystem Affected Versions Fixed Version
october/october
 Packagist
< 3.7.14
3.7.14
october/october
 Packagist
≥ 4.0.0
< 4.1.10
4.1.10

References

GitHub Advisory / Wiki ADVISORY
https://github.com/octobercms/october/security/advisories/GHSA-h6jm-f4hh-fw27
NVD — CVE-2026-26274 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-26274
October/october Source Repository REPOSITORY
https://github.com/octobercms/october

Frequently Asked Questions

What is CVE-2026-26274?
CVE-2026-26274 is a security vulnerability in October/october involving October CMS has Safe Mode Bypass via Twig Database Write Operations under CWE-863: Incorrect Authorization.
Which October/october versions are affected?
Affected versions include releases prior to 3.7.14, 4.1.10 across affected packages: october/october.
What version fixes CVE-2026-26274?
Upgrading to 3.7.14, 4.1.10 (or the latest patched release for your respective branch) resolves the vulnerability.
Is october/october affected?
Yes, october/october is affected in releases prior to 3.7.14, 4.1.10. Upgrade your dependency to 3.7.14, 4.1.10 or later.
What is the CVSS score of CVE-2026-26274?
CVE-2026-26274 has a CVSS v3.1 base score of 6.6 (MODERATE) with vector string CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H.
What CWE is associated with CVE-2026-26274?
CVE-2026-26274 is classified under CWE-863: Incorrect Authorization (The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check.).
How can I check Packagist dependencies for CVE-2026-26274?
Run the dependency tree command: 'inspect dependencies for october/october'. 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-h6jm-f4hh-fw27",
  "modified" : "2026-04-24T21:08:44Z",
  "published" : "2026-04-21T16:44:19Z",
  "aliases" : [ "CVE-2026-26274" ],
  "summary" : "October CMS has Safe Mode Bypass via Twig Database Write Operations",
  "details" : "A vulnerability was identified in the Twig sandbox security policy that allowed database write operations when `cms.safe_mode` is enabled. Backend users with Developer permissions could use Twig template markup to execute insert, update, and delete operations on any database table through the query builder, which is included in the sandbox allow-list.\n\n### Impact\n- Arbitrary database writes including modification or deletion of any table\n- Requires authenticated backend access with Developer permissions\n- Only relevant when `cms.safe_mode` is enabled (otherwise direct PHP injection is already possible)\n\n### Patches\nThe vulnerability has been patched in v3.7.14 and v4.1.10. Write operations such as `insert`, `update`, `delete`, and `truncate` are now blocked on query builder and model objects within the Twig sandbox. All users are encouraged to upgrade to the latest patched version.\n\n### Workarounds\nIf upgrading immediately is not possible:\n- Restrict Developer tool access to fully trusted administrators only\n\n### Reporter\n- Reported by [Chris Alupului](https://github.com/neosprings)",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Packagist",
      "name" : "october/october"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "3.7.14"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Packagist",
      "name" : "october/october"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "4.0.0"
      }, {
        "fixed" : "4.1.10"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/octobercms/october/security/advisories/GHSA-h6jm-f4hh-fw27"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-26274"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/octobercms/october"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-184", "CWE-863" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-04-21T16:44:19Z",
    "nvd_published_at" : "2026-04-21T17:16:30Z"
  }
}