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Vulnerability record · CVE-2021-27963 · published 5 March 2021

CVE-2021-27963: Sfcyazilim sonlogger missing authentication for critical function vulnerability

SSfcyazilim · Sonlogger

SonLogger before 6.4.1 is affected by user creation with any user permissions profile (e.g., SuperAdmin). An anonymous user can send a POST request to /User/saveUser without any authentication or session header.

8.2 CVSS 3.1 High EPSS 2.4% · top 16.3% CWE-306 · Missing authentication for critical function
8.2CVSS 3.1 base score, v2 6.4
2.4%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
4References, 2 tagged exploit
17 Jun 2026Last modified by NVD

Description

SonLogger before 6.4.1 is affected by user creation with any user permissions profile (e.g., SuperAdmin). An anonymous user can send a POST request to /User/saveUser without any authentication or session header.

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

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://github.com/erberkan/SonLogger-vulns ExploitThird Party Advisory
https://www.sonlogger.com/releasenotes Release NotesVendor Advisory
https://github.com/erberkan/SonLogger-vulns ExploitThird Party Advisory
https://www.sonlogger.com/releasenotes Release NotesVendor Advisory

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2021-27963), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.