What’s Vulnerable › Vulnerabilities

CVE-2023-38431

• Severity: critical (CVSS 9.1 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2023-07-18 · updated 2026-06-17
• Weakness: CWE-125

Description

An issue was discovered in the Linux kernel before 6.3.8. fs/smb/server/connection.c in ksmbd does not validate the relationship between the NetBIOS header's length field and the SMB header sizes, via pdu_size in ksmbd_conn_handler_loop, leading to an out-of-bounds read.

Affected products

• Linux kernel: from 5.15 before 5.15.145; from 5.16 before 6.1.34; from 6.2 before 6.3.8 — fixed in 5.15.145, 6.1.34, 6.3.8
• NetApp H300S: all versions
• NetApp H410S: all versions
• NetApp H500S: all versions
• NetApp H700S: all versions
• NetApp Solidfire & Hci Management Node: all versions

How to fix

Upgrade to a fixed version: Linux kernel 5.15.145, 6.1.34, 6.3.8. Check the vendor advisory for mitigations.

References

• https://cdn.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.3.8
• https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/fs/smb/server?id=368ba06881c395f1c9a7ba22203cf8d78b4addc0
• https://security.netapp.com/advisory/ntap-20230824-0011/
• https://cdn.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.3.8
• https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/fs/smb/server?id=368ba06881c395f1c9a7ba22203cf8d78b4addc0
• https://security.netapp.com/advisory/ntap-20230824-0011/

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