As últimas versões do PHP foram liberados recentemente (versão do PHP 7.3.9, 7.2.22 e 7.1.32 em vários ramos) para solucionar diversas vulnerabilidades altamente críticos em seu núcleo e bibliotecas empacotados. The most dangerous of these vulnerabilities are the ones that could lead to remote code execution.
Por pouco 80% de todos os sites executados em PHP. Mais particularmente, “PHP é usado por 78.9% de todos os sites cuja linguagem de programação do servidor conhecemos”, according to W3Techs statistics. This means that the vulnerabilities could affect a large number of web applications that utilize PHP, including websites that run on content management systems such as WordPress and Drupal, pesquisadores alertam.
Mais especificamente, depending on the affected codebase in a PHP app, the worst-case scenario attacks based on these flaws could allow threat actors to execute arbitrary code in the context of the application. In case of a failed attempt of exploitation, a denial-of-service (DoS) condition could be triggered on affected systems.
More about CVE-2019-13224
The worst of the flaws is known under the CVE-2019-13224 advisory. According to the official CVE-2019-13224 description, a vulnerabilidade é "a use-after-free in onig_new_deluxe() in regext.c in Oniguruma 6.9.2” that could allow attackers to potentially cause information disclosure, negação de serviço, or possibly code execution by providing a crafted regular expression.
The attacker provides a pair of a regex pattern and a string, with a multi-byte encoding that gets handled by onig_new_deluxe(). Oniguruma issues often affect Ruby, as well as common optional libraries for PHP and Rust, the advisory reads.
The already available patches address vulnerabilities in cURL, Exif function, FastCGI Process Manager, OPcache. There is currently no information of active attacks against these flaws. Contudo, immediate patching is required, so consider updating to the latest PHP version version 7.3.9, 7.2.22, ou 7.1.32 o mais cedo possível. It should be noted that PHP version 7.1.32 fixes the CVE-2019-13224 flaw.