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.

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

EPSS: 0.006 (45.9th percentile) — read the EPSS interpretation.

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.

Affected products

Phreesoft Phreebooks — versions 5.2.3

Weakness classification (CWE)

CWE-434 — Unrestricted Upload of File with Dangerous Type

References

ExploitDB-49524 (exploit)
Official Vendor Homepage (product)
ExploitDB-46645 (exploit)
Web Shell Payload Gist (product)
VulnCheck Advisory: PhreeBooks 5.2.3 - Remote Code Execution (third-party-advisory)

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.