Arbitrary file upload in Hashthemes Hash Form

CVE-2026-81780

Unauthenticated Arbitrary File Upload in Hash Form <= 1.4.2 versions.

Vulnerability class: Unrestricted File Upload

Published · last modified .

CVSS v3 metric

CVSS v3 base score 10.0 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.005 (42.9th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 43rd percentile — 42.9% 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-2026-81780: held from 0.003 to 0.005.

EPSS over last 30 days · oldest: 0.003 · newest: 0.005 · change: +0.002

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2026-81780?
CVE-2026-81780 is a critical-severity vulnerability in Hashthemes Hash Form, classified under Unrestricted Upload of File with Dangerous Type. CVSS score: 10.0/10. Published 2026-08-31.
How severe is CVE-2026-81780?
Critical severity. CVSS v3 base score is 10.0 out of 10.
Is CVE-2026-81780 known to be exploited?
2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.