CVE-2026-78834
CMSimple CoAuthors Plugin Remote Code Execution
Description
A code execution vulnerability exists in CMSimple 5.22 in the CoAuthors plugin. An authenticated low-privileged user who can modify page content and provide controlled imported content can trigger server-side execution by referencing crafted external or uploaded text content through the affected content import feature.
INFO
Published Date :
Sept. 8, 2026, 8:18 p.m.
Last Modified :
Sept. 9, 2026, 4:04 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-78834
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | HIGH | 134c704f-9b21-4f2e-91b3-4a467353bcc0 |
Solution
- Update the CoAuthors plugin.
- Remove or disable the affected plugin.
- Review user permissions for content modification.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-78834.
| URL | Resource |
|---|---|
| https://gist.github.com/AEQ3/574cb644306776a9ff1a0de30b085e62 | |
| https://github.com/AEQ3/CVE/issues/1 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-78834 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-78834
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-78834 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-78834 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Sep. 09, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Added CWE CWE-94 Added SSVC {'id': 'CVE-2026-78834', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-09-09T13:05:22.526332Z'} -
New CVE Received by [email protected]
Sep. 08, 2026
Action Type Old Value New Value Added Description A code execution vulnerability exists in CMSimple 5.22 in the CoAuthors plugin. An authenticated low-privileged user who can modify page content and provide controlled imported content can trigger server-side execution by referencing crafted external or uploaded text content through the affected content import feature. Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/78xxx/CVE-2026-78834.json">CVE-2026-78834</a> Added Reference https://gist.github.com/AEQ3/574cb644306776a9ff1a0de30b085e62 Added Reference https://github.com/AEQ3/CVE/issues/1