Heap-based Buffer Overflow Affecting nginx package, versions <1.22.1-9+deb12u7


Severity

Recommended
0.0
high
0
10

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Threat Intelligence

Exploit Maturity
Proof of Concept
EPSS
66.04% (100th percentile)

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  • Snyk IDSNYK-ECHOLATEST-NGINX-18011612
  • published18 Jul 2026
  • disclosed13 May 2026

Introduced: 13 May 2026

CVE-2026-42945  (opens in a new tab)
CWE-122  (opens in a new tab)

How to fix?

Upgrade Echo:latest nginx to version 1.22.1-9+deb12u7 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream nginx package and not the nginx package as distributed by Echo. See How to fix? for Echo:latest relevant fixed versions and status.

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.

CVSS Base Scores

version 3.1