DRUPAL-CORE-2026-006 BIT-drupal-2026-55804 CVE-2026-55804
Drupal core contains a chain of methods that could be exploitable when an insecure deserialization vulnerability exists on the site.
- Severity
- 5.9 / 10
- Medium · CVSS 3.1
- Exploit chance (EPSS)
- 0.35%
- Chance of exploitation in the next 30 days. Higher than 28.93% of scored vulnerabilities.
- Known exploited
- No
- Not in CISA's catalog
- Weakness
- CWE-915 Improperly Controlled Modification of Dynamically-Determined Object Attributes
- Fix
11.3.12- Upgrade drupal/core to this version or later
Description
Drupal core contains a chain of methods that could be exploitable when an insecure deserialization vulnerability exists on the site. This so-called "gadget chain" presents no direct threat, but is a vector that can be used to achieve remote code execution or SQL injection if the application deserializes untrusted data due to another vulnerability.
This issue is not directly exploitable.
This issue is mitigated by the fact that in order for it to be exploitable, a separate vulnerability must be present to allow an attacker to pass unsafe input to unserialize().
Affected versions
Packagist
| Package | Vulnerable | Fixed in |
|---|---|---|
| drupal/core | < 10.5.12>= 10.6.0, < 10.6.11>= 11.2.0, < 11.2.14>= 11.3.0, < 11.3.12>= 11.0.0, < 11.1.0>= 11.1.0, < 11.2.0 |
10.5.1210.6.1111.1.011.2.011.2.1411.3.12 |
How to fix
Move to the fixed version or later with your package manager, update the lockfile, and run your tests. If the package only arrives through another dependency, upgrade that dependency first. If none of its releases pulls a fixed version yet, force the version with your package manager's override.
drupal/core Packagist → 11.3.12
- composer
composer require drupal/core:^11.3.12
Severity breakdown
CVSS 3.1 5.9
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:N
- Attack vector
- Network
- Attack complexity
- High
- Privileges required
- High
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- None
Weakness
CWE-915: Improperly Controlled Modification of Dynamically-Determined Object Attributes
The product receives input from an upstream component that specifies multiple attributes, properties, or fields that are to be initialized or updated in an object, but it does not properly control which attributes can be modified.
How to prevent it
- Implementation: If available, use features of the language or framework that allow specification of allowlists of attributes or fields that are allowed to be modified. If possible, prefer allowlists over denylists. For applications written with Ruby on Rails, use the attr_accessible (allowlist) or attr_protected (denylist) macros in each class that may be used in mass assignment.
- Architecture and Design, Implementation: If available, use the signing/sealing features of the programming language to assure that deserialized data has not been tainted. For example, a hash-based message authentication code (HMAC) could be used to ensure that data has not been modified.
- Implementation: For any externally-influenced input, check the input against an allowlist of internal object attributes or fields that are allowed to be modified.
- Implementation, Architecture and Design: Refactor the code so that object attributes or fields do not need to be dynamically identified, and only expose getter/setter functionality for the intended attributes.
References
Other links
Timeline
- Published
- Last updated by the source
- Latest EPSS score
Related advisories
| Advisory | Severity | Why it's related |
|---|---|---|
| DRUPAL-CORE-2026-004 Drupal Core has a SQL Injection issue | Critical Known exploited | Also affects drupal/core |
| CVE-2020-28949 Multiple vulnerabilities through filename manipulation in Archive_Tar | High Known exploited | Also affects drupal/core |
| CVE-2020-13671 Drupal core Unrestricted Upload of File with Dangerous Type | High Known exploited | Also affects drupal/core |
| CVE-2019-6340 Drupal Core Remote Code Execution Vulnerability | High Known exploited | Also affects drupal/core |
| CVE-2018-7602 Drupal Core Remote Code Execution Vulnerability | Critical Known exploited | Also affects drupal/core |
| CVE-2018-7600 Drupal Core Remote Code Execution Vulnerability | Critical Known exploited | Also affects drupal/core |
| DRUPAL-CORE-2026-016 The Navigation module doesn't sufficiently sanitize certain attributes, which can lead to a cross-site scripting (XSS) vulnerability. | Not rated yet | Also affects drupal/core |
| DRUPAL-CORE-2026-015 The Drupal core Link module provides a field type that can be used for internal and external URLs. | Not rated yet | Also affects drupal/core |
Credits: Michael Maturi (michaelmaturi)
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