CVE-2026-89632 (GCVE-0-2026-89632)
Vulnerability from cvelistv5
Published
2026-09-11 19:45
Modified
2026-10-21 12:48
Severity ?
8.2 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: smb: client: fix use-before-check of ReparseDataLength in reparse_buf_ptr() reparse_buf_ptr() reads buf->ReparseDataLength before checking that count covers the full fixed header: buf = (struct reparse_data_buffer *)((u8 *)io + off); len = sizeof(*buf); /* 8 bytes */ rdlen = le16_to_cpu(buf->ReparseDataLength); /* offset 4, 2 bytes */ if (count < len || count < rdlen + len) /* check comes after */ struct reparse_data_buffer has ReparseDataLength at offset 4. If a server returns OutputCount < 6, the read at offset 4-5 reaches past the end of the received data. The off+count bounds against iov_len were already validated, but that does not protect against count being smaller than sizeof(*buf). Split the check: verify count >= sizeof(*buf) before reading ReparseDataLength, then verify count covers the data region.
References
Impacted products
Vendor Product Version
Linux Linux Version: a158bb66b1373866d9fd5997565a58a573085539
Version: 67ec9949b0dfe78c99e110dd975eb7dc5645630c
Version: 67ec9949b0dfe78c99e110dd975eb7dc5645630c
Version: 6.6.32   ≤
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