CVE-2026-34443
FreeScout: SSRF protection bypass via broken CIDR check in checkIpByMask()
Description
FreeScout is a free help desk and shared inbox built with PHP's Laravel framework. Prior to version 1.8.211, checkIpByMask() in app/Misc/Helper.php checks whether the input IP contains a / character. Plain IP addresses never contain /, so the function always returns false without checking any CIDR ranges. The entire 10.0.0.0/8 and 172.16.0.0/12 private ranges are unprotected. This issue has been patched in version 1.8.211.
INFO
Published Date :
March 31, 2026, 10:16 p.m.
Last Modified :
April 13, 2026, 3:14 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | [email protected] | ||||
| CVSS 4.0 | MEDIUM | [email protected] |
Solution
- Update FreeScout to version 1.8.211 or later.
- Verify the IP address validation logic.
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-2026-34443.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-34443 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-2026-34443
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-2026-34443 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-34443 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.
-
Initial Analysis by [email protected]
Apr. 13, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N Added CPE Configuration OR *cpe:2.3:a:freescout:freescout:*:*:*:*:*:*:*:* versions up to (excluding) 1.8.211 Added Reference Type GitHub, Inc.: https://github.com/freescout-help-desk/freescout/commit/ca6d5bb572d3e8f52a0e654a8623a53cb0fdd580 Types: Patch Added Reference Type GitHub, Inc.: https://github.com/freescout-help-desk/freescout/releases/tag/1.8.211 Types: Release Notes Added Reference Type GitHub, Inc.: https://github.com/freescout-help-desk/freescout/security/advisories/GHSA-c9v3-4c59-x5q2 Types: Exploit, Vendor Advisory -
New CVE Received by [email protected]
Mar. 31, 2026
Action Type Old Value New Value Added Description FreeScout is a free help desk and shared inbox built with PHP's Laravel framework. Prior to version 1.8.211, checkIpByMask() in app/Misc/Helper.php checks whether the input IP contains a / character. Plain IP addresses never contain /, so the function always returns false without checking any CIDR ranges. The entire 10.0.0.0/8 and 172.16.0.0/12 private ranges are unprotected. This issue has been patched in version 1.8.211. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CWE CWE-918 Added Reference https://github.com/freescout-help-desk/freescout/commit/ca6d5bb572d3e8f52a0e654a8623a53cb0fdd580 Added Reference https://github.com/freescout-help-desk/freescout/releases/tag/1.8.211 Added Reference https://github.com/freescout-help-desk/freescout/security/advisories/GHSA-c9v3-4c59-x5q2