CVE-2026-84223Network attack vectorHinoki check available

Stored XSS via unsanitized SVG uploads

Published Sep 20, 2026 · Updated Sep 20, 2026

Stored XSS in Themeum Kirki 6.0.0 through 6.3.0 allows remote authenticated users to execute JavaScript via uploaded SVG files. Kirki enables SVG uploads site-wide without sanitizing active content, so attacker-supplied JavaScript is served from the site's own origin. Author-level access is required to upload the file, and execution occurs when another user opens it, exposing that user's browser session to same-origin script actions.

CVSS severity4.6
Medium
EPSS probability0.43%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Stored XSS in Themeum Kirki 6.0.0 through 6.3.0 allows remote authenticated users to execute JavaScript via uploaded SVG files. Kirki enables SVG uploads site-wide without sanitizing active content, so attacker-supplied JavaScript is served from the site's own origin. Author-level access is required to upload the file, and execution occurs when another user opens it, exposing that user's browser session to same-origin script actions.

The record

CVE
CVE-2026-84223
Published
Sep 20, 2026
Updated
Sep 20, 2026
Vendor
Themeum
Product
Kirki
Classifications
CWE-79, T1203
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 20, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 20, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=6.0.0 <6.3.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Themeum · Kirkiversion=6.0.0 <6.3.1

Published CVSS scores

3.5NVDAV:N/AC:M/Au:S/C:N/I:P/A:N
4.6NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Activity data is delayed. The latest report is Sep 28, 2026.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1203Exploitation for Client Execution

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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