CVE-2019-19768 Use after free in n/a

High 7.5 Published 12 Dec 2019 Updated 5 Aug 2024

A use-after-free vulnerability in the Linux kernel's blktrace function allows attackers to potentially execute code or escalate privileges.

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

What is CVE-2019-19768?

CVE-2019-19768 is a high-severity use after free vulnerability in Linux kernel, published on 12 Dec 2019. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

In the Linux kernel 5.4.0-rc2, there is a use-after-free (read) in the __blk_add_trace function in kernel/trace/blktrace.c (which is used to fill out a blk_io_trace structure and place it in a per-cpu sub-buffer).

Weakness: CWE-416

Which versions are affected by CVE-2019-19768?

It affects 1 product.

Linux distribution packages (25)

`bpftool` Red Hat:rhel_e4s:8.0::baseos	All versions	`0:4.18.0-80.18.1.el8_0`
`bpftool-debuginfo` Red Hat:rhel_e4s:8.0::baseos	All versions	`0:4.18.0-80.18.1.el8_0`
`kernel` Red Hat:rhel_e4s:8.0::baseos	All versions	`0:4.18.0-80.18.1.el8_0`
`kernel-abi-whitelists` Red Hat:rhel_e4s:8.0::baseos	All versions	`0:4.18.0-80.18.1.el8_0`
`kernel-core` Red Hat:rhel_e4s:8.0::baseos	All versions	`0:4.18.0-80.18.1.el8_0`
`kernel-debug` Red Hat:rhel_e4s:8.0::baseos	All versions	`0:4.18.0-80.18.1.el8_0`
`kernel-debug-core` Red Hat:rhel_e4s:8.0::baseos	All versions	`0:4.18.0-80.18.1.el8_0`
`kernel-debug-debuginfo` Red Hat:rhel_e4s:8.0::baseos	All versions	`0:4.18.0-80.18.1.el8_0`
`kernel-debug-devel` Red Hat:rhel_e4s:8.0::baseos	All versions	`0:4.18.0-80.18.1.el8_0`
`kernel-debug-modules` Red Hat:rhel_e4s:8.0::baseos	All versions	`0:4.18.0-80.18.1.el8_0`
`kernel-debug-modules-extra` Red Hat:rhel_e4s:8.0::baseos	All versions	`0:4.18.0-80.18.1.el8_0`
`kernel-debuginfo` Red Hat:rhel_e4s:8.0::baseos	All versions	`0:4.18.0-80.18.1.el8_0`
`kernel-debuginfo-common-ppc64le` Red Hat:rhel_e4s:8.0::baseos	All versions	`0:4.18.0-80.18.1.el8_0`
`kernel-debuginfo-common-x86_64` Red Hat:rhel_e4s:8.0::baseos	All versions	`0:4.18.0-80.18.1.el8_0`
`kernel-devel` Red Hat:rhel_e4s:8.0::baseos	All versions	`0:4.18.0-80.18.1.el8_0`
`kernel-doc` Red Hat:rhel_e4s:8.0::baseos	All versions	`0:4.18.0-80.18.1.el8_0`
`kernel-modules` Red Hat:rhel_e4s:8.0::baseos	All versions	`0:4.18.0-80.18.1.el8_0`
`kernel-modules-extra` Red Hat:rhel_e4s:8.0::baseos	All versions	`0:4.18.0-80.18.1.el8_0`
`kernel-tools` Red Hat:rhel_e4s:8.0::baseos	All versions	`0:4.18.0-80.18.1.el8_0`
`kernel-tools-debuginfo` Red Hat:rhel_e4s:8.0::baseos	All versions	`0:4.18.0-80.18.1.el8_0`
`kernel-tools-libs` Red Hat:rhel_e4s:8.0::baseos	All versions	`0:4.18.0-80.18.1.el8_0`
`perf` Red Hat:rhel_e4s:8.0::baseos	All versions	`0:4.18.0-80.18.1.el8_0`
`perf-debuginfo` Red Hat:rhel_e4s:8.0::baseos	All versions	`0:4.18.0-80.18.1.el8_0`
`python3-perf` Red Hat:rhel_e4s:8.0::baseos	All versions	`0:4.18.0-80.18.1.el8_0`
`python3-perf-debuginfo` Red Hat:rhel_e4s:8.0::baseos	All versions	`0:4.18.0-80.18.1.el8_0`

Products include Linux kernel.

How do I fix CVE-2019-19768?

Apply the vendor's patch.

Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.

Is CVE-2019-19768 being exploited?

There is no known exploitation of CVE-2019-19768 in the wild and no public exploit code.

All Linux kernel vulnerabilities

Sources

Also known as DEBIAN-CVE-2019-19768, GHSA-j7c5-8q8x-hgwf, RHSA-2020:1966, UBUNTU-CVE-2019-19768.