Arbitrary file upload in Phreesoft Phreebooks

CVE-2021-47904

PhreeBooks 5.2.3 contains an authenticated file upload vulnerability in the Image Manager that allows remote code execution. Attackers can upload a malicious PHP web shell by exploiting unrestricted file type uploads to gain command execution on the server.

Vulnerability class: Unrestricted File Upload

Published · last modified .

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.007 (51.2th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 51st percentile — 51.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2021-47904: held from 0.006 to 0.007.

EPSS over last 30 days · oldest: 0.006 · newest: 0.007 · change: +0.001

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2021-47904?
CVE-2021-47904 is a high-severity vulnerability in Phreesoft Phreebooks, classified under Unrestricted Upload of File with Dangerous Type. CVSS score: 8.8/10. Published 2026-01-23.
How severe is CVE-2021-47904?
High severity. CVSS v3 base score is 8.8 out of 10.