CVE-2026-43185
CRITICAL
9.8
CVSS 3.1
Description
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix signededness bug in smb_direct_prepare_negotiation()
smb_direct_prepare_negotiation() casts an unsigned __u32 value
from sp->max_recv_size and req->preferred_send_size to a signed
int before computing min_t(int, ...). A maliciously provided
preferred_send_size of 0x80000000 will return as smaller than
max_recv_size, and then be used to set the maximum allowed
alowed receive size for the next message.
By sending a second message with a large value (>1420 bytes)
the attacker can then achieve a heap buffer overflow.
This fix replaces min_t(int, ...) with min_t(u32)
Metadata
Severity & Metrics
9.8
CRITICAL CVSS 3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected products (2)
| Vendor | Product | Platform | Versions |
|---|---|---|---|
| Linux | Linux | — | 0626e6641f6b467447c81dd7678a69c66f7746cf < ceae058eb707ddd0d68f0872f9d9f23b7c30c37b, 0626e6641f6b467447c81dd7678a69c66f7746cf < 55abc475d096da4a5356b6efb0cfdc6156bc1550, 0626e6641f6b467447c81dd7678a69c66f7746cf < 6b4f875aac344cdd52a1f34cc70ed2f874a65757 |
| Linux | Linux | — | 5.15, 0 < 5.15, 6.18.16 ≤ 6.18.*, 6.19.6 ≤ 6.19.* … |
CVSS scores (1)
| Score | Severity | Version | Source | Vector |
|---|---|---|---|---|
| 9.8 | CRITICAL | 3.1 | cna | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
References (3)