CVE-2018-14633 Memory corruption in kernel

High 7.0 Published 25 Sep 2018 Updated 5 Aug 2024

Unauthenticated remote attackers can trigger a stack buffer overflow in the Linux kernel iSCSI target, causing denial of service or potential data exposure.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: Available

What is CVE-2018-14633?

CVE-2018-14633 is a high-severity memory corruption vulnerability in Canonical Ubuntu Linux, published on 25 Sep 2018. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

A security flaw was found in the chap_server_compute_md5() function in the ISCSI target code in the Linux kernel in a way an authentication request from an ISCSI initiator is processed. An unauthenticated remote attacker can cause a stack buffer overflow and smash up to 17 bytes of the stack. The attack requires the iSCSI target to be enabled on the victim host. Depending on how the target's code was built (i.e. depending on a compiler, compile flags and hardware architecture) an attack may lead to a system crash and thus to a denial-of-service or possibly to a non-authorized access to data exported by an iSCSI target. Due to the nature of the flaw, privilege escalation cannot be fully ruled out, although we believe it is highly unlikely. Kernel versions 4.18.x, 4.14.x and 3.10.x are believed to be vulnerable.

Weakness: CWE-787, CWE-121

Which versions are affected by CVE-2018-14633?

It affects 8 products.

Linux distribution packages (3)

`kgraft-patch-SLE12-SP3_Update_18` SUSE:Linux Enterprise Live Patching 12 SP3	All versions	`2-2.1`
`kgraft-patch-SLE12-SP3_Update_19` SUSE:Linux Enterprise Live Patching 12 SP3	All versions	`2-2.1`
`kgraft-patch-SLE12-SP3_Update_20` SUSE:Linux Enterprise Live Patching 12 SP3	All versions	`2-2.1`

Products include Canonical Ubuntu Linux, Debian Debian Linux, Linux kernel, Redhat Enterprise Linux Eus, Redhat Enterprise Linux Server, Redhat Enterprise Linux Server Aus and 2 more.

How do I fix CVE-2018-14633?

Apply the vendor's patch.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2018-14633 being exploited?

There is no known exploitation of CVE-2018-14633 in the wild and no public exploit code.

All Canonical Ubuntu Linux vulnerabilities

Sources

Also known as DEBIAN-CVE-2018-14633, GHSA-88p5-45fx-5x87, SUSE-SU-2018:3268-1, SUSE-SU-2018:3867-1, UBUNTU-CVE-2018-14633.