CVE-2026-79590 Null dereference in n/a
An attacker can crash the mruby application by providing a specially crafted Ruby source file that triggers a NULL pointer dereference in the Prism parser.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-79590?
CVE-2026-79590 is a medium-severity vulnerability in n/a, published on 10 Sep 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
A NULL pointer dereference vulnerability exists in the Prism parser component of mruby 4.0.0. An attacker can provide a specially crafted Ruby source file that triggers the parser to pass a NULL pointer to nonnull string handling functions, resulting in undefined behavior and application crash.
Weakness: CWE-476
Which versions are affected by CVE-2026-79590?
How do I fix CVE-2026-79590?
No fix has been published for CVE-2026-79590 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-79590 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-79590 exists.
Sources
Also known as DEBIAN-CVE-2026-79590, GHSA-q9f2-rhj2-x3xg, UBUNTU-CVE-2026-79590.