CVE-2023-6606: Kernel: out-of-bounds read vulnerability in smbcalcsize

Severity: high (CVSS 7.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2023-12-08 · updated 2026-10-14
Weakness: CWE-125

Description

An out-of-bounds read vulnerability was found in smbCalcSize in fs/smb/client/netmisc.c in the Linux Kernel. This issue could allow a local attacker to crash the system or leak internal kernel information.

Affected products

Linux kernel: from 6.4.1 before 6.7; 6.4, 6.4-rc4, 6.4-rc5, 6.4-rc6, 6.4-rc7, 6.7-rc1 (+5) — fixed in 6.7
Red Hat Enterprise Linux: 8.0, 9.0
RedHat Enterprise Linux Eus: 9.2, 9.4
RedHat Enterprise Linux Server Aus: 9.2, 9.4
RedHat Enterprise Linux Server For Power Little Endian Update Services For Sap Solutions: 9.2, 9.2_ppc64le

How to fix

Upgrade to a fixed version: Linux kernel 6.7. Check the vendor advisory for mitigations.

References

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