Description
In the Linux kernel, the following vulnerability has been resolved:
hfs: Replace BUG_ON with error handling for CNID count checks
In a06ec283e125 next_id, folder_count, and file_count in the super block
info were expanded to 64 bits, and BUG_ONs were added to detect
overflow. This triggered an error reported by syzbot: if the MDB is
corrupted, the BUG_ON is triggered. This patch replaces this mechanism
with proper error handling and resolves the syzbot reported bug.
Singed-off-by: Jori Koolstra <jkoolstra@xs4all.nl>
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Linux | Linux | 6.18 | 6.18.57 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | linux | 6.19.6-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 25.10 | linux +8 | No fix yet | — |
| Ubuntu 24.04 LTS | linux-riscv +25 | No fix yet | — |
| Ubuntu 22.04 LTS | linux-riscv +32 | No fix yet | — |
| Ubuntu 20.04 LTS | linux-gke +28 | No fix yet | — |
| Ubuntu 18.04 LTS | linux-gcp +14 | No fix yet | — |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 16.04 LTS | linux-hwe-edge | No fix yet | — |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime-6.14 +1 | No fix yet | — |
Advisories 1
- WID-SEC-2026-1405 Linux Kernel: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 12, 2026