High severity · published Apr 22, 2026
CVE-2026-31433
ksmbd: fix potencial OOB in get_file_all_info() for compound requests
8.8
CVSS
0.6%
EPSS
No
On KEV
Description
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix potencial OOB in get_file_all_info() for compound requests
When a compound request consists of QUERY_DIRECTORY + QUERY_INFO
(FILE_ALL_INFORMATION) and the first command consumes nearly the entire
max_trans_size, get_file_all_info() would blindly call smbConvertToUTF16()
with PATH_MAX, causing out-of-bounds write beyond the response buffer.
In get_file_all_info(), there was a missing validation check for
the client-provided OutputBufferLength before copying the filename into
FileName field of the smb2_file_all_info structure.
If the filename length exceeds the available buffer space, it could lead to
potential buffer overflows or memory corruption during smbConvertToUTF16
conversion. This calculating the actual free buffer size using
smb2_calc_max_out_buf_len() and returning -EINVAL if the buffer is
insufficient and updating smbConvertToUTF16 to use the actual filename
length (clamped by PATH_MAX) to ensure a safe copy operation.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 49% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KE
Kernel · Linux
5.15.145 before 5.15.203; 6.1.71 before 6.1.168; 6.6 before 6.6.131; 6.7 before 6.12.80; 6.13 before 6.18.21; 6.19 before 6.19.11; +5 more · source: NVD
LI
Linux · Linux
f2283680a80571ca82d710bc6ecd8f8beac67d63 before 3a852f9d1c981fb14f6bf4e24999e0ea8088a7d7; 9f297df20d93411c0b4ddad7f88ba04a7cd36e77 before 4cca3eff2099b18672934a39cee70aed835d652c; e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d before 358cdaa1f7fbf2712cb4c5f6b59cb9a5c673c5fe; e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d before 7aec5a769d2356cbf344d85bcfd36de592ac96a5; e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d before b0cd9725fe2bcc9f37d096b132318a9060373f5d; e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d before 9d7032851d6f5adbe2739601ca456c0ad3b422f0; +4 more · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-31433
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-31433
Patch
https://git.kernel.org/stable/c/358cdaa1f7fbf2712cb4c5f6b59cb9a5c673c5fe
Patch
https://git.kernel.org/stable/c/3a852f9d1c981fb14f6bf4e24999e0ea8088a7d7
Patch
https://git.kernel.org/stable/c/4cca3eff2099b18672934a39cee70aed835d652c
Patch
https://git.kernel.org/stable/c/7aec5a769d2356cbf344d85bcfd36de592ac96a5
Patch
https://git.kernel.org/stable/c/9d7032851d6f5adbe2739601ca456c0ad3b422f0
Patch
https://git.kernel.org/stable/c/b0cd9725fe2bcc9f37d096b132318a9060373f5d
More from Kernel
9.8
CVE-2025-39682
tls: fix handling of zero-length records on the rx_list
8.8
CVE-2026-53266
netfilter: bridge: make ebt_snat ARP rewrite writable
8.8
CVE-2013-6282
Linux Kernel Improper Input Validation Vulnerability
8.4
CVE-2022-0185
Linux Kernel Heap-Based Buffer Overflow Vulnerability
8.4
CVE-2013-2094
Linux Kernel Privilege Escalation Vulnerability
