What is CVE-2021-30209?

CVE-2021-30209 is a medium-severity vulnerability in Textpattern, classified under Unrestricted Upload of File with Dangerous Type. CVSS score: 6.5/10. Published 2021-04-15.

How severe is CVE-2021-30209?

Medium severity. CVSS v3 base score is 6.5 out of 10.

Arbitrary file upload in Textpattern

CVE-2021-30209

Textpattern V4.8.4 contains an arbitrary file upload vulnerability where a plug-in can be loaded in the background without any security verification, which may lead to obtaining system permissions.

Vulnerability class: Unrestricted File Upload

Published 2021-04-15 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N.

EPSS exploit prediction

EPSS: 0.008 (53.3th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 53rd percentile — 53.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.008 · newest: 0.008 · change: 0.000

Affected products

Textpattern — versions 4.8.4

Weakness classification (CWE)

CWE-434 — Unrestricted Upload of File with Dangerous Type

References

github.com/textpattern/textpattern/issues/1655 (Exploit, Third Party Advisory, Issue Tracking)

Frequently asked questions

What is CVE-2021-30209?: CVE-2021-30209 is a medium-severity vulnerability in Textpattern, classified under Unrestricted Upload of File with Dangerous Type. CVSS score: 6.5/10. Published 2021-04-15.
How severe is CVE-2021-30209?: Medium severity. CVSS v3 base score is 6.5 out of 10.