What is CVE-2023-34738?

CVE-2023-34738 is a critical-severity vulnerability in Chemex, classified under Unrestricted Upload of File with Dangerous Type. CVSS score: 9.8/10. Published 2023-06-29.

How severe is CVE-2023-34738?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Arbitrary file upload in Chemex

CVE-2023-34738

Chemex through 3.7.1 is vulnerable to arbitrary file upload.

Vulnerability class: Unrestricted File Upload

Published 2023-06-29 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.008 (54.4th percentile), scored 2026-10-08.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 54th percentile — 54.4% 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

Chemex

Weakness classification (CWE)

CWE-434 — Unrestricted Upload of File with Dangerous Type

References

github.com/celaraze/chemex/issues/64 (Exploit, Issue Tracking)

Frequently asked questions

What is CVE-2023-34738?: CVE-2023-34738 is a critical-severity vulnerability in Chemex, classified under Unrestricted Upload of File with Dangerous Type. CVSS score: 9.8/10. Published 2023-06-29.
How severe is CVE-2023-34738?: Critical severity. CVSS v3 base score is 9.8 out of 10.