CVE-2026-43362

Updated on 08 May 2026

Severity

8.1 High severity

Details

CVSS score
8.1

Overview

About vulnerability

In the Linux kernel, the following vulnerability has been resolved: smb: client: fix in-place encryption corruption in SMB2_write() SMB2_write() places write payload in iov[1..n] as part of rq_iov. smb3_init_transform_rq() pointer-shares rq_iov, so crypt_message() encrypts iov[1] in-place, replacing the original plaintext with ciphertext. On a replayable error, the retry sends the same iov[1] which now contains ciphertext instead of the original data, resulting in corruption. The corruption is most likely to be observed when connections are unstable, as reconnects trigger write retries that re-send the already-encrypted data. This affects SFU mknod, MF symlinks, etc. On kernels before 6.10 (prior to the netfs conversion), sync writes also used this path and were similarly affected. The async write path wasn’t unaffected as it uses rq_iter which gets deep-copied. Fix by moving the write payload into rq_iter via iov_iter_kvec(), so smb3_init_transform_rq() deep-copies it before encryption. A flaw was found in the Linux kernel’s Server Message Block (SMB) client. This vulnerability allows a remote attacker to cause data corruption. When an SMB client attempts to write data over an unstable connection, the in-place encryption process can lead to already encrypted data being re-sent during write retries. This results in the original plaintext being replaced by ciphertext, causing data integrity issues.

Details

KernelCare state

Live-patch status from KernelCare for each operating system.

Operating system Status Covered kernels
Debian 13 Planned
Ubuntu 24.04 Planned