CVE-2026-51926 (CVSS 7.5)

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.

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CVSS v3.1 Score

7.5

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

EPSS — Exploit Prediction

0.0036

Probability of exploitation

0.29%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-203 CWE-203

References

Other References

https://docuform.de https://gist.github.com/ZeroBreach-GmbH

Frequently Asked Questions

What is CVE-2026-51926? +

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. It has a CVSS v3.1 base score of 7.5 (HIGH).

How severe is CVE-2026-51926? +

CVE-2026-51926 has a CVSS v3.1 score of 7.5 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0036, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-51926? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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