CVE-2026-46155: smb/client: fix out-of-bounds read in smb2_compound_op()
In the Linux kernel, the following vulnerability has been resolved:
smb/client: fix out-of-bounds read in smb2compoundop()
If a server sends a truncated response but a large OutputBufferLength, and terminates the EA list early, checkwsleas() returns success without validating that the entire OutputBufferLength fits within iovlen.
Then smb2compoundop() does: memcpy(idata->wsl.eas, data[0], size[0]);
Where size[0] is OutputBufferLength. If iovlen is smaller than size[0], memcpy can read beyond the end of the rspiov allocation and leak adjacent kernel heap memory.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 6.6.141.1-1
Event History
Frequently Asked Questions
What is the severity of CVE-2026-46155?
The severity of CVE-2026-46155 is critical with a score of 9.1.
What type of vulnerability is CVE-2026-46155?
CVE-2026-46155 is an out-of-bounds read vulnerability affecting the smb/client in the Linux kernel.
How do I fix CVE-2026-46155?
CVE-2026-46155 can be fixed by applying the available patch.
Which software versions are affected by CVE-2026-46155?
CVE-2026-46155 affects the Linux kernel and Microsoft azl3 kernel 6.6.139.1-1.
What impact does CVE-2026-46155 have on systems?
CVE-2026-46155 could allow an attacker to exploit the out-of-bounds read and potentially access sensitive information.