CVE-2026-67189

MEDIUM
Published Aug 19, 2026 Modified Aug 25, 2026 CWE-79

Description

pfSense Plus before 26.07 and pfSense CE through 2.8.1 contain a stored cross-site scripting vulnerability in the Traffic Graphs top-talkers feature, where PTR records returned by reverse DNS lookups are incorporated without sanitization into AJAX responses and rendered as HTML through a DOM sink in the administrator interface. An attacker who controls a PTR record and generates sufficient traffic to appear as a top talker can execute arbitrary JavaScript in an administrator's browser, gaining access to the authenticated session context and same-origin access to the firewall management interface, enabling account creation and arbitrary OS command execution.

Is your site exposed to CVE-2026-67189?

Run a free security scan — no signup, results in seconds.

CVSS v3.1 Score

6.1
MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

EPSS — Exploit Prediction

0.0053
Probability of exploitation
0.43%
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-79 Cross-site Scripting (XSS)

References

Frequently Asked Questions

What is CVE-2026-67189? +
pfSense Plus before 26.07 and pfSense CE through 2.8.1 contain a stored cross-site scripting vulnerability in the Traffic Graphs top-talkers feature, where PTR records returned by reverse DNS lookups are incorporated without sanitization into AJAX responses and rendered as HTML through a DOM sink in the administrator interface. An attacker who controls a PTR record and generates sufficient traffic to appear as a top talker can execute arbitrary JavaScript in an administrator's browser, gaining access to the authenticated session context and same-origin access to the firewall management interface, enabling account creation and arbitrary OS command execution. It has a CVSS v3.1 base score of 6.1 (MEDIUM).
How severe is CVE-2026-67189? +
CVE-2026-67189 has a CVSS v3.1 score of 6.1 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance. The EPSS score is 0.0053, placing it in the 0th percentile for exploitation probability.
How do I check if I'm vulnerable to CVE-2026-67189? +
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.

Related Vulnerabilities

Don't wait for an exploit

Scan your website for vulnerabilities like CVE-2026-67189 — free, no signup required.