Joomla Extension - getk2.org - Stored-XSS in K2 extension for Joomla < 2.26

published 2026-06-25 4mo ago modified 2026-10-25 17d ago also EUVD-2026-39445

cvss: 3.4; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 21%
public exploits: 0; none known

A Joomla user with K2 "create item" rights (Author tier by default) can submit an article whose `embedVideo` POST field contains a raw `<script>` tag; K2 stores it verbatim and renders it unescaped to any visitor of the article page.

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CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 4mo ago (2026-06-25)

Exploit prediction

0.28% chance of exploitation in the next 30 days, higher than 21% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by	version	score	vector
CISA ADP	3.1	3.4	CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:N/A:N
CNA	3.1	3.4	CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:N/A:N

Affected products

getk2.org K2 extension for Joomla

Classification

Weakness

CWE-79 Improper Neutralization of Input During Web Page Generation

References

getk2.org /
product

Sources

CVE List CVE-2026-48940
NVD CVE-2026-48940

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.