A libwebp security update has been released for Ubuntu Linux 18.04 LTS.

[USN-6369-2] libwebp vulnerability

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Ubuntu Security Notice USN-6369-2
September 28, 2023

libwebp vulnerability
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 18.04 LTS (Available with Ubuntu Pro)

Summary:

libwebp could be made to crash or run programs if it opened a specially
crafted file.

Software Description:
- libwebp: Lossy compression of digital photographic images.

Details:

USN-6369-1 fixed a vulnerability in libwebp. This update provides the
corresponding update for Ubuntu 18.04 LTS.

Original advisory details:

It was discovered that libwebp incorrectly handled certain malformed
images. If a user or automated system were tricked into opening a
specially crafted image file, a remote attacker could use this issue to
cause libwebp to crash, resulting in a denial of service, or possibly
execute arbitrary code.

Update instructions:

The problem can be corrected by updating your system to the following
package versions:

Ubuntu 18.04 LTS (Available with Ubuntu Pro):
libwebp6 0.6.1-2ubuntu0.18.04.2+esm1
libwebpdemux2 0.6.1-2ubuntu0.18.04.2+esm1
libwebpmux3 0.6.1-2ubuntu0.18.04.2+esm1

In general, a standard system update will make all the necessary changes.

References:
https://ubuntu.com/security/notices/USN-6369-2
https://ubuntu.com/security/notices/USN-6369-1
CVE-2023-4863