A PHP security update has been released for Ubuntu Linux 16.04 ESM.

USN-5300-1: PHP vulnerabilities

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Ubuntu Security Notice USN-5300-1
February 22, 2022

php7.0 vulnerabilities
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 16.04 ESM

Summary:

Several security issues were fixed in PHP.

Software Description:
- php7.0: HTML-embedded scripting language interpreter

Details:

It was discovered that PHP incorrectly handled certain scripts.
An attacker could possibly use this issue to cause a denial of service.
(CVE-2015-9253, CVE-2017-8923, CVE-2017-9118, CVE-2017-9120)

It was discovered that PHP incorrectly handled certain inputs.
An attacker could possibly use this issue to cause a denial of service,
or possibly obtain sensitive information. (CVE-2017-9119)

It was discovered that PHP incorrectly handled certain scripts with XML
parsing functions.
An attacker could possibly use this issue to obtain sensitive information.
(CVE-2021-21707)

Update instructions:

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

Ubuntu 16.04 ESM:
php7.0-cgi 7.0.33-0ubuntu0.16.04.16+esm3
php7.0-cli 7.0.33-0ubuntu0.16.04.16+esm3
php7.0-fpm 7.0.33-0ubuntu0.16.04.16+esm3

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

References:
https://ubuntu.com/security/notices/USN-5300-1
CVE-2015-9253, CVE-2017-8923, CVE-2017-9118, CVE-2017-9119,
CVE-2017-9120, CVE-2021-21707