CVE-2023-54250

ksmbd: avoid out of bounds access in decode_preauth_ctxt()

HIGH
8.2
CVSS Score
Published: December 30, 2025 at 12:15 PM UTC
Updated: August 5, 2026 at 10:24 AM UTC
1 product affected across 1 vendorLinux Kernel

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Severity
HIGH8.2
Exploit prediction
EPSS 0.5%

Description

In the Linux kernel, the following vulnerability has been resolved: ksmbd: avoid out of bounds access in decode_preauth_ctxt() Confirm that the accessed pneg_ctxt->HashAlgorithms address sits within the SMB request boundary; deassemble_neg_contexts() only checks that the eight byte smb2_neg_context header + (client controlled) DataLength are within the packet boundary, which is insufficient. Checking for sizeof(struct smb2_preauth_neg_context) is overkill given that the type currently assumes SMB311_SALT_SIZE bytes of trailing Salt.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

5.15 ≤ v < 5.15.1455.15 ≤ v < 6.1.255.15 ≤ v < 6.2.125.15 ≤ v < 6.35.15e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9
Vendor states this is fixed in 39f5b4b313b445c980a2a295bed28228c29228ed (fixed)
Vendor states this is fixed in a2f6ded41bec1d3be643c80a5eb97f1680309001 (fixed)
Vendor states this is fixed in e7067a446264a7514fa1cfaa4052cdb6803bc6a2 (fixed)
Vendor states this is fixed in f02edb9debbd36f44efa7567031485892c7df60d (fixed)
Vendor states this is fixed in 5.15 (unaffected)
Vendor states this is fixed in 5.15.145 (unaffected)
Vendor states this is fixed in 6.1.25 (unaffected)
Vendor states this is fixed in 6.2.12 (unaffected)
Vendor states this is fixed in 6.3 (unaffected)

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

CVSS

8.2HIGHLinux
Vector?

Quick Info

StatusDEFERRED

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