What is CVE-2026-2099?

CVE-2026-2099 is a medium-severity vulnerability in Flowring Agentflow, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2026-02-10.

How severe is CVE-2026-2099?

Medium severity. CVSS v3 base score is 5.4 out of 10.

XSS in Flowring Agentflow

CVE-2026-2099

AgentFlow developed by Flowring has a Stored Cross-Site Scripting vulnerability, allowing authenticated remote attackers to inject persistent JavaScript codes that are executed in users' browsers upon page load.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2026-02-10 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.002 (5.8th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 6th percentile — 5.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.000

Affected products

Flowring Agentflow — versions 4.0.*

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

www.twcert.org.tw/tw/cp-132-10699-49c0b-1.html (Third Party Advisory, third-party-advisory)
www.twcert.org.tw/en/cp-139-10700-3534d-2.html (Third Party Advisory, third-party-advisory)

Frequently asked questions

What is CVE-2026-2099?: CVE-2026-2099 is a medium-severity vulnerability in Flowring Agentflow, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2026-02-10.
How severe is CVE-2026-2099?: Medium severity. CVSS v3 base score is 5.4 out of 10.