CVE-2026-78839 File upload in n/a
Attackers can execute arbitrary code by uploading a crafted .phar file to MachForm, posing a critical risk to web application security.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-78839?
CVE-2026-78839 is a high-severity vulnerability in n/a, published on 4 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
An arbitrary file upload vulnerability in AppNitro MachForm v30 allows attackers to execute arbitrary code via uploading a crafted .phar file.
Weakness: CWE-434
Which versions are affected by CVE-2026-78839?
How do I fix CVE-2026-78839?
No fix has been published for CVE-2026-78839 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-78839 being exploited?
There is no known exploitation of CVE-2026-78839 in the wild and no public exploit code.
Public exploit code: 1 proofs of concept on GitHub.
Sources
Also known as GHSA-5w46-w28q-f95g.