CVE-2026-51926
docuForm FSM Client User Enumeration Vulnerability
Description
An issue in docuForm GmbH FSM Client v.11.11c allows a remote attacker to obtain sensitive information via the login.php component. A vulnerability was identified in the authentication mechanism that allows user enumeration through the login interface. An attacker can differentiate between valid and invalid usernames based on variations in server responses. This information can be leveraged to identify existing accounts and facilitate further attacks, including brute-force or credential stuffing.
INFO
Published Date :
July 9, 2026, 9:16 p.m.
Last Modified :
Oct. 25, 2026, 5:10 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-51926
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 FSM Client to the latest version.
- Harden authentication responses.
- Implement rate limiting on login attempts.
- Enhance input validation for usernames.
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-2026-51926.
| URL | Resource |
|---|---|
| https://docuform.de | |
| https://gist.github.com/ZeroBreach-GmbH |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-51926 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-2026-51926
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-2026-51926 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-51926 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 Translated by [email protected]
Oct. 25, 2026
Action Type Old Value New Value Added Translation Title: GmbH FSM Client de docuForm, Description: Un problema en docuForm GmbH FSM Client v.11.11c permite a un atacante remoto obtener información sensible a través del componente login.php. Se identificó una vulnerabilidad en el mecanismo de autenticación que permite la enumeración de usuarios a través de la interfaz de inicio de sesión. Un atacante puede diferenciar entre nombres de usuario válidos e inválidos basándose en variaciones en las respuestas del servidor. Esta información puede ser aprovechada para identificar cuentas existentes y facilitar ataques posteriores, incluyendo fuerza bruta o relleno de credenciales. -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jul. 10, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N Added CWE CWE-203 Added SSVC {'id': 'CVE-2026-51926', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-07-10T15:34:56.289158Z'} -
New CVE Received by [email protected]
Jul. 09, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'n/a', 'product': 'n/a', 'versions': [{'status': 'affected', 'version': 'n/a'}]}] Added Description An issue in docuForm GmbH FSM Client v.11.11c allows a remote attacker to obtain sensitive information via the login.php component. A vulnerability was identified in the authentication mechanism that allows user enumeration through the login interface. An attacker can differentiate between valid and invalid usernames based on variations in server responses. This information can be leveraged to identify existing accounts and facilitate further attacks, including brute-force or credential stuffing. Added Reference https://docuform.de Added Reference https://gist.github.com/ZeroBreach-GmbH