CVE-2026-124743 Busybox: divide-by-zero and heap over-read in the volume_id hfs+ prober
A crafted HFS+ filesystem image can crash BusyBox via divide-by-zero, preventing device resolution; Linux systems mounting untrusted media should care.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Harmful if only installed
- No
- Needs a specific call
- No
- Fix
- None listed
What is CVE-2026-124743?
CVE-2026-124743 is a medium-severity denial of service vulnerability in Red Hat Enterprise Linux 6, published on 11 Nov 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Official description
A flaw was found in BusyBox. When processing filesystem metadata, the volume identification component does not properly validate header values in HFS+ filesystems. An attacker able to attach a storage device or supply a specially crafted filesystem image can trigger an application crash, resulting in a Denial of Service (DoS) and preventing device resolution.
Weakness: CWE-369
Which versions are affected by CVE-2026-124743?
An affected version is exposed as installed. No special setting or call is needed.
How do I fix CVE-2026-124743?
No fix has been published for CVE-2026-124743 yet. Limit exposure of the affected software until one is available.
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-2026-124743 being exploited?
There is no known exploitation of CVE-2026-124743 in the wild and no public exploit code.
Sources
Also known as GHSA-gjcv-9jxm-vqjv, UBUNTU-CVE-2026-124743.