Heap-based Buffer Overflow Affecting nginx package, versions [0.6.27,1.30.1)
Threat Intelligence
Snyk has a proof-of-concept or detailed explanation of how to exploit this vulnerability.
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Start learning- Snyk IDSNYK-UNMANAGED-NGINX-16679754
- published14 May 2026
- disclosed13 May 2026
- creditZhenpeng (Leo) Lin
Introduced: 13 May 2026
CVE-2026-42945 (opens in a new tab)How to fix?
Upgrade nginx to version 1.30.1 or higher.
Overview
Affected versions of this package are vulnerable to Heap-based Buffer Overflow in the ngx_http_rewrite_module process when a rewrite directive is followed by a rewrite, if, or set directive and an unnamed Perl-Compatible Regular Expression (PCRE) capture (such as $1, $2) is used with a replacement string containing a question mark (?). An attacker can cause a heap buffer overflow in the worker process, potentially leading to process restart or, if Address Space Layout Randomization (ASLR) is disabled, arbitrary code execution by sending specially crafted HTTP requests. This is only exploitable if ASLR is disabled for code execution to occur.