Arbitrary file upload in Flexhex
CVE-2019-25627
FlexHEX 2.71 contains a local buffer overflow vulnerability in the Stream Name field that allows local attackers to execute arbitrary code by triggering a structured exception handler (SEH) overflow. Attackers can craft a malicious text file with carefully aligned shellcode and SEH chain pointers, paste the contents into the Stream Name dialog, and execute arbitrary commands like calc.exe when the exception handler is triggered.
Vulnerability class: Unrestricted File Upload
EPSS: 0.003 (17.4th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 8.4 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Flexhex — versions 2.71
Weakness classification (CWE)
References
- disclosure@vulncheck.com (Exploit, VDB Entry, exploit)
- disclosure@vulncheck.com (Product, product, Broken Link)
- disclosure@vulncheck.com (Product, product, Broken Link)
- disclosure@vulncheck.com (Third Party Advisory, third-party-advisory)
Frequently asked questions
- What is CVE-2019-25627?
- CVE-2019-25627 is a high-severity vulnerability in Flexhex, classified under Unrestricted Upload of File with Dangerous Type. CVSS score: 8.4/10. Published 2026-03-24.
- How severe is CVE-2019-25627?
- High severity. CVSS v3 base score is 8.4 out of 10.