cms: Improperly Controlled Modification of Dynamically-Determined Object Attributes
CVE-2026-72778 is a high-severity improperly controlled modification of dynamically-determined object attributes vulnerability in cms from Craft CMS, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. The record lists versions 5.10.6, 4.18.2 as the first without the flaw, so updating cms to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.8% chance of exploitation within 30 days, higher than 57% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update cms to 5.10.6 or 4.18.2, whichever matches your release line, or a later version.
- Read the advisory on github.com for workarounds and exact fixed builds.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Craft CMS | cms | 5.0.0-RC1 up to, but not including, 5.10.6; 4.0.0-RC1 up to, but not including, 4.18.2 | 5.10.6, 4.18.2 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (vulncheck.com).
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 8.7 | High | CNA (vulncheck.com) |
| CVSS 3.1 | 8.8 | High | CNA (vulncheck.com) |
Official description
Craft CMS versions from 4.0.0-RC1 before 4.18.2 and from 5.0.0-RC1 before 5.10.6 contain an authenticated remote code execution vulnerability in the control panel element-search condition handling. Craft cleanses the outer request-controlled condition array via Component::cleanseConfig(), but Conditions::createCondition() later decodes and merges the JSON string in condition.config without re-running cleanseConfig() on the decoded configuration. Because condition.config is a JSON string during the first cleanse, Yii special config keys such as 'as ...' and 'on ...' can be hidden inside it and, after JSON decoding, are interpreted by Yii as behavior/event configuration during FieldLayout object creation. An attacker with an authenticated control panel session (and a valid CSRF token) can exploit this to execute operating system commands as the PHP/web user.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: 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 developers prevent this class of flaw
- 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.
- 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.
- For any externally-influenced input, check the input against an allowlist of internal object attributes or fields that are allowed to be modified.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Other references
Other vulnerabilities in cms
- 9.8 Critical severity
- 8.8 High severity
- 7.5 High severity
- 9.8 Critical severity
- 8.2 High severity
- 8.8 High severity
Recent Improperly Controlled Modification of Dynamically-Determined Object Attributes vulnerabilities
- 8.8 High severity
- 8.4 High severity
- 8.7 High severity
- 7.5 High severity
- 8.1 High severity
- 8.1 High severity
Spotted an error? Tell us.