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vulnerability

Alma Linux: CVE-2026-42945: Critical: nginx security update (Multiple Advisories)

Severity
9
CVSS
(AV:N/AC:M/Au:N/C:C/I:C/A:C)
Published
May 18, 2026
Added
May 19, 2026
Modified
May 27, 2026

Description

NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_rewrite_module module. This vulnerability exists when the rewrite directive is followed by a rewrite, if, or set directive and an unnamed Perl-Compatible Regular Expression (PCRE) capture (for example, $1, $2) with a replacement string that includes a question mark (?). An unauthenticated attacker along with conditions beyond its control can exploit this vulnerability by sending crafted HTTP requests. This may cause a heap buffer overflow in the NGINX worker process leading to a restart. Additionally, attackers can execute code on systems with Address Space Layout Randomization (ASLR) disabled or when the attacker can bypass ASLR.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Solutions

alma-upgrade-nginxalma-upgrade-nginx-all-modulesalma-upgrade-nginx-corealma-upgrade-nginx-filesystemalma-upgrade-nginx-mod-develalma-upgrade-nginx-mod-http-image-filteralma-upgrade-nginx-mod-http-perlalma-upgrade-nginx-mod-http-xslt-filteralma-upgrade-nginx-mod-mailalma-upgrade-nginx-mod-stream
Title
Rapid7 Labs

2026 Global Threat Landscape Report

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