CVE-2026-34567
CI4MS: Blogs Posts (Categories) Full Account Takeover for All-Roles & Privilege-Escalation via Stored DOM XSS
CI4MS is a CodeIgniter 4-based CMS skeleton that delivers a production-ready, modular architecture with RBAC authorization and theme support. Prior to version 0.31.0.0, the application fails to properly sanitize user-controlled input when creating or editing blog posts within the Categories section. An attacker can inject a malicious JavaScript payload into the Categories content, which is then stored server-side. This stored payload is later rendered unsafely when the Categories are viewed via blog posts, without proper output encoding, leading to stored cross-site scripting (XSS). This issue has been patched in version 0.31.0.0.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- Low
- Availability
- Low
Exploit likelihood
What each source reports
CVE List Score used
9.1
CI4MS: Blogs Posts (Categories) Full Account Takeover for All-Roles & Privilege-Escalation via Stored DOM XSS
CI4MS is a CodeIgniter 4-based CMS skeleton that delivers a production-ready, modular architecture with RBAC authorization and theme support. Prior to version 0.31.0.0, the application fails to properly sanitize user-controlled input when creating or editing blog posts within the Categories section. An attacker can inject a malicious JavaScript payload into the Categories content, which is then stored server-side. This stored payload is later rendered unsafely when the Categories are viewed via blog posts, without proper output encoding, leading to stored cross-site scripting (XSS). This issue has been patched in version 0.31.0.0.
- Record
CVE-2026-34567- CVSS 3.1
- 9.1 Critical
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:L - Weakness
- CWE-79
- Updated
- 2026-11-02
EUVDEUVD-2026-18081
9.1
CI4MS is a CodeIgniter 4-based CMS skeleton that delivers a production-ready, modular architecture with RBAC authorization and theme support. Prior to version 0.31.0.0, the application fails to properly sanitize user-controlled input when creating or editing blog posts within the Categories section. An attacker can inject a malicious JavaScript payload into the Categories content, which is then stored server-side. This stored payload is later rendered unsafely when the Categories are viewed via blog posts, without proper output encoding, leading to stored cross-site scripting (XSS). This issue has been patched in version 0.31.0.0.
- Record
EUVD-2026-18081- CVSS 3.1
- 9.1 Critical
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:L - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-r33w-c82v-x5v7
9.1
CI4MS: Blogs Posts (Categories) Full Account Takeover for All-Roles & Privilege-Escalation via Stored DOM XSS
Summary
Vulnerability: Blogs Posts (Categories) Full Account Takeover for All-Roles & Privilege-Escalation via Stored DOM XSS
- Stored Cross-Site Scripting via Unsanitized Blog Post Content in Blog Management (Categories)
Description
The application fails to properly sanitize user-controlled input when creating or editing blog posts within the Categories section. An attacker can inject a malicious JavaScript payload into the Categories content, which is then stored server-side.
This stored payload is later rendered unsafely when the Categories are viewed via blog posts, without proper output encoding, leading to stored cross-site scripting (XSS).
Affected Functionality
- Blog post Categories creation functionality
- Blog post Categories editing functionality
- Blog post Categories storage and retrieval logic
Attack Scenario
- An attacker creates or edits a blog post Category to include a malicious XSS payload in the category description or name.
- The application stores this content without sanitization or encoding.
- The payload persists and executes whenever the category is viewed within the blog posts section, leading to the execution of arbitrary JavaScript in the victim’s browser.
Impact
- Persistent Stored XSS
- Execution of arbitrary JavaScript in victims’ browsers
- Privilege escalation when viewed by administrators or privileged users within the Categories functionality
- Full administrator account takeover through Categories access
- Full account takeover across all roles via Categories pages
- Full compromise of the entire application via XSS in Categories
Endpoints:
/backend/blogs/create(Categories specific)/backend/blogs/(Categories view)/blog/{id}(Rendered blog post under Categories)
Steps To Reproduce (POC)
- Go to the Categories section of the blog management panel.
- Create a new category or edit an existing category.
- Insert an XSS payload into the category content, such as:
<img src=x onerror=alert(document.domain)> - Save or publish the Categories.
- View the category via the blog posts in the administrative panel or public blog page under the Categories section.
- Notice the XSS payload executing automatically when the Category is viewed in the Blog Posts.
Remediation
-
Avoid unsafe DOM manipulation methods: Do not use
.html(),innerHTML, or similar sink functions in client-side JavaScript or server-side templating (e.g., PHP). Even when user input flowing into these sinks is not immediately apparent, they can introduce Cross-Site Scripting (XSS) vulnerabilities that an attacker may exploit. -
Apply output encoding: Implement HTML entity encoding on all user-controlled data before rendering it in the browser. This helps neutralize potentially malicious input.
-
Implement input sanitization: Ensure that all user-supplied input is properly sanitized before processing or output. Currently, no sanitization mechanisms are in place, which should be addressed as a priority.
-
Enforce security headers and cookie attributes:
- Content Security Policy (CSP): Define and enforce a strict CSP to limit the execution of unauthorized scripts.
- HttpOnly flag: Set the
HttpOnlyattribute on session cookies to prevent client-side script access. - SameSite attribute: Configure the
SameSitecookie attribute to mitigate Cross-Site Request Forgery (CSRF) risks. - Secure flag: Ensure all cookies are transmitted only over HTTPS by enabling the
Secureattribute.
These measures collectively reduce the impact of XSS and help prevent escalation paths such as CSRF via XSS.
Ready Video POC:
https://mega.nz/file/SAdVxK7b#kFW_sFOim_d_1AnVcpwvzOEV4MHv33LLooL4Xa_Ymgg
- Record
GHSA-r33w-c82v-x5v7- CVSS 3.1
- 9.1 Critical
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:L - Weakness
- CWE-79
- Updated
- 2026-11-02
NVD
9.1
CI4MS is a CodeIgniter 4-based CMS skeleton that delivers a production-ready, modular architecture with RBAC authorization and theme support. Prior to version 0.31.0.0, the application fails to properly sanitize user-controlled input when creating or editing blog posts within the Categories section. An attacker can inject a malicious JavaScript payload into the Categories content, which is then stored server-side. This stored payload is later rendered unsafely when the Categories are viewed via blog posts, without proper output encoding, leading to stored cross-site scripting (XSS). This issue has been patched in version 0.31.0.0.
- Record
CVE-2026-34567- CVSS 3.1
- 9.1 Critical
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:L - CVSS 3.1
- 9.0 Critical
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H - Weakness
- CWE-79
- Updated
- 2026-11-02
OSV
9.1
CI4MS: Blogs Posts (Categories) Full Account Takeover for All-Roles & Privilege-Escalation via Stored DOM XSS
CI4MS is a CodeIgniter 4-based CMS skeleton that delivers a production-ready, modular architecture with RBAC authorization and theme support. Prior to version 0.31.0.0, the application fails to properly sanitize user-controlled input when creating or editing blog posts within the Categories section. An attacker can inject a malicious JavaScript payload into the Categories content, which is then stored server-side. This stored payload is later rendered unsafely when the Categories are viewed via blog posts, without proper output encoding, leading to stored cross-site scripting (XSS). This issue has been patched in version 0.31.0.0.
- Record
CVE-2026-34567- CVSS 3.1
- 9.1 Critical
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:L - Weakness
- CWE-79
- Updated
- 2026-11-02
OSVGHSA-r33w-c82v-x5v7
9.1
CI4MS: Blogs Posts (Categories) Full Account Takeover for All-Roles & Privilege-Escalation via Stored DOM XSS
Summary
Vulnerability: Blogs Posts (Categories) Full Account Takeover for All-Roles & Privilege-Escalation via Stored DOM XSS
- Stored Cross-Site Scripting via Unsanitized Blog Post Content in Blog Management (Categories)
Description
The application fails to properly sanitize user-controlled input when creating or editing blog posts within the Categories section. An attacker can inject a malicious JavaScript payload into the Categories content, which is then stored server-side.
This stored payload is later rendered unsafely when the Categories are viewed via blog posts, without proper output encoding, leading to stored cross-site scripting (XSS).
Affected Functionality
- Blog post Categories creation functionality
- Blog post Categories editing functionality
- Blog post Categories storage and retrieval logic
Attack Scenario
- An attacker creates or edits a blog post Category to include a malicious XSS payload in the category description or name.
- The application stores this content without sanitization or encoding.
- The payload persists and executes whenever the category is viewed within the blog posts section, leading to the execution of arbitrary JavaScript in the victim’s browser.
Impact
- Persistent Stored XSS
- Execution of arbitrary JavaScript in victims’ browsers
- Privilege escalation when viewed by administrators or privileged users within the Categories functionality
- Full administrator account takeover through Categories access
- Full account takeover across all roles via Categories pages
- Full compromise of the entire application via XSS in Categories
Endpoints:
/backend/blogs/create(Categories specific)/backend/blogs/(Categories view)/blog/{id}(Rendered blog post under Categories)
Steps To Reproduce (POC)
- Go to the Categories section of the blog management panel.
- Create a new category or edit an existing category.
- Insert an XSS payload into the category content, such as:
<img src=x onerror=alert(document.domain)> - Save or publish the Categories.
- View the category via the blog posts in the administrative panel or public blog page under the Categories section.
- Notice the XSS payload executing automatically when the Category is viewed in the Blog Posts.
Remediation
-
Avoid unsafe DOM manipulation methods: Do not use
.html(),innerHTML, or similar sink functions in client-side JavaScript or server-side templating (e.g., PHP). Even when user input flowing into these sinks is not immediately apparent, they can introduce Cross-Site Scripting (XSS) vulnerabilities that an attacker may exploit. -
Apply output encoding: Implement HTML entity encoding on all user-controlled data before rendering it in the browser. This helps neutralize potentially malicious input.
-
Implement input sanitization: Ensure that all user-supplied input is properly sanitized before processing or output. Currently, no sanitization mechanisms are in place, which should be addressed as a priority.
-
Enforce security headers and cookie attributes:
- Content Security Policy (CSP): Define and enforce a strict CSP to limit the execution of unauthorized scripts.
- HttpOnly flag: Set the
HttpOnlyattribute on session cookies to prevent client-side script access. - SameSite attribute: Configure the
SameSitecookie attribute to mitigate Cross-Site Request Forgery (CSRF) risks. - Secure flag: Ensure all cookies are transmitted only over HTTPS by enabling the
Secureattribute.
These measures collectively reduce the impact of XSS and help prevent escalation paths such as CSRF via XSS.
Ready Video POC:
https://mega.nz/file/SAdVxK7b#kFW_sFOim_d_1AnVcpwvzOEV4MHv33LLooL4Xa_Ymgg
- Record
GHSA-r33w-c82v-x5v7- CVSS 3.1
- 9.1 Critical
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:L - Weakness
- CWE-79
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
ci4-cms-erp/ci4msPackagist |
through 0.28.6.0 | 0.31.0.0 |
ci4-cms-erp/ci4msPackagist |
before 0.31.0.0, plus listed versions 0.21.00.21.10.21.20.21.30.21.3.1 Show 42 moreShow less0.21.3.20.21.3.30.21.3.40.21.3.50.21.3.60.21.3.70.23.0.00.23.0.10.23.0.20.23.1.00.24.0.00.24.0.160.24.0.180.24.0.190.24.0.200.24.0.270.24.0.420.24.0.450.24.0.600.25.0.00.25.0.10.25.0.20.25.0.300.25.0.390.25.0.430.25.1.00.25.2.00.25.3.00.26.0.00.26.1.00.26.2.00.26.3.00.26.3.10.26.3.20.26.3.30.26.3.40.27.0.00.28.0.00.28.3.00.28.4.00.28.5.00.28.6.0 |
0.31.0.0 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-34567 is a critical vulnerability (CVSS 9.1) in Ci4-cms-erp Ci4ms, published April 1, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.27%, the 19th percentile. Fixed in ci4-cms-erp/ci4ms 0.31.0.0.
References
github.com/ci4-cms-erp/ci4ms/security/advisories/GHSA-r33w-c82v-x5v7
github.com/ci4-cms-erp/ci4ms/releases/tag/0.31.0.0
nvd.nist.gov/vuln/detail/CVE-2026-34567
github.com/advisories/GHSA-r33w-c82v-x5v7
github.com/CVEProject/cvelistV5/tree/main/cves/2026/34xxx/CVE-2026-34567.json
github.com/ci4-cms-erp/ci4ms