{"id":"AZL-88116","summary":"CVE-2026-9256 affecting package nginx for versions less than 1.28.3-4","details":"NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_rewrite_module module. This vulnerability exists when a rewrite directive uses a regex pattern with distinct, overlapping Perl-Compatible Regular Expression (PCRE) captures (for example, ^/((.*))$) and a replacement string that references multiple such captures (for example, $1$2) in a redirect or arguments context. An unauthenticated attacker along with conditions beyond their 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. \n\n\nNote: Software versions which have reached End of Technical Support (EoTS) are not evaluated.","modified":"2026-09-20T05:33:47Z","published":"2026-05-22T15:16:27Z","upstream":["CVE-2026-9256"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-9256"}],"affected":[{"package":{"name":"nginx","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/nginx"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.28.3-4"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-88116.json"}}],"schema_version":"1.9.0"}