CVE-2026-98204 Input: rmi_smbus - fix out-of-bounds read in rmi_smb_write_block()
A local attacker can trigger an out-of-bounds read in the RMI SMBus driver, potentially leaking kernel memory or causing a system crash.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-98204?
CVE-2026-98204 is a memory corruption vulnerability in Linux, published on 6 Oct 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
Input: rmi_smbus - fix out-of-bounds read in rmi_smb_write_block()
When chunking writes into SMBus blocks in rmi_smb_write_block(), the loop calculates block_len using the original total length (len) instead of the remaining length (cur_len).
If len is greater than 32 bytes (SMB_MAX_COUNT), block_len remains 32 for every iteration, even on the final partial chunk where fewer than 32 bytes remain. This causes smb_block_write() to read 32 bytes from the advanced data buffer pointer, reading past the end of the input buffer.
Fix this by calculating block_len using cur_len and advancing the buffer and address pointers by block_len.
Which versions are affected by CVE-2026-98204?
How do I fix CVE-2026-98204?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-98204 being exploited?
There is no known exploitation of CVE-2026-98204 in the wild and no public exploit code.
Sources
Also known as AZL-106233, BELL-CVE-2026-98204, DEBIAN-CVE-2026-98204, GHSA-qm76-89x6-cmqm, UBUNTU-CVE-2026-98204.