CVE-2026-15383: XSS (CVSS 6.1)

Description

The Blog Floating Button WordPress plugin through 1.4.20 does not sanitize or escape the visitor User-Agent header, which it stores through an unauthenticated tracking REST endpoint and later renders unescaped in an administrator report page. This allows an unauthenticated attacker to store a malicious script that executes in the session of any administrator who views the access report, leading to site takeover.

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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

0.0016

Probability of exploitation

0.06%

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

Other References

https://wpscan.com/vulnerability/45e5d74e-6f7b-499b-ae25-74fe1bc8d18d/

Frequently Asked Questions

What is CVE-2026-15383? +

The Blog Floating Button WordPress plugin through 1.4.20 does not sanitize or escape the visitor User-Agent header, which it stores through an unauthenticated tracking REST endpoint and later renders unescaped in an administrator report page. This allows an unauthenticated attacker to store a malicious script that executes in the session of any administrator who views the access report, leading to site takeover. It has a CVSS v3.1 base score of 6.1 (MEDIUM).

How severe is CVE-2026-15383? +

CVE-2026-15383 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 0.0016, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-15383? +

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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CVE-2026-15383