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Fencer Intel
medium 6.5

CVE-2026-39666 json

WordPress Hello Bar Popup Builder plugin <= 1.5.1 - Cross Site Scripting (XSS) vulnerability

published 7mo ago modified 3mo ago also EUVD-2026-20340

cvss
6.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 5%
public exploits
0
none known

Summary

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in telepathy Hello Bar Popup Builder hellobar allows DOM-Based XSS.This issue affects Hello Bar Popup Builder: from n/a through <= 1.5.1.

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CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
7mo ago

Exploit prediction

0.17% chance of exploitation in the next 30 days, higher than 5% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
CNA 3.1 6.5 CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:L
CISA ADP 3.1 6.5 CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:L

Affected products

  • telepathy Hello Bar Popup Builder

Classification

Weakness
  • CWE-79 Improper Neutralization of Input During Web Page Generation
Technology feeds

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.