CVE-2026-4833 Orc discount Markdown markdown.c compile recursion
A local attacker can cause a crash in the Orc discount Markdown library by providing deeply nested blockquote input, leading to denial of service.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-4833?
CVE-2026-4833 is a medium-severity denial of service vulnerability in Orc discount, published on 26 Mar 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
A weakness has been identified in Orc discount up to 3.0.1.2. This issue affects the function compile of the file markdown.c of the component Markdown Handler. This manipulation causes uncontrolled recursion. The attack is restricted to local execution. The exploit has been made available to the public and could be used for attacks. The project maintainer confirms: "[I]f you feed it an infinitely deep blockquote input it will crash. (...) [T]his is a duplicate of an old bug that I've been working on."
Which versions are affected by CVE-2026-4833?
Linux distribution packages (1)
discount openSUSE:Tumbleweed | All versions | 3.0.2.0-1.1 |
How do I fix CVE-2026-4833?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-4833 being exploited?
There is no known exploitation of CVE-2026-4833 in the wild and no public exploit code.
Sources
Also known as AZL-81020, AZL-81062, DEBIAN-CVE-2026-4833, GHSA-9f9p-gp89-cxxh, UBUNTU-CVE-2026-4833, openSUSE-SU-2026:11786-1.