NGINX
CVE-2026-42934: NGINX ngx_http_charset_module vulnerability
NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_charset_module module.
Published
Automatic summary from the vendor's CVE record. We haven't written a full analysis of this vulnerability yet.
Affected and fixed versions
| Product / branch | Fixed in |
|---|---|
| NGINX Plus R37 | Not affected |
| NGINX Plus R36 | R36 P4 or later |
| NGINX Plus R32 | R32 P6 or later |
| NGINX Open Source 1.31 | Not affected |
| NGINX Open Source 0.3 | 1.30.1 or later |
Always confirm against the vendor advisory, which lists every fixed hotfix.
What it is
NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_charset_module module. When charset, source_charset, and charset_map and proxy_pass with disabled buffering ("off") directives are configured, unauthenticated attackers can send requests that with conditions beyond the attackers' control to cause a heap buffer over-read in the NGINX worker process, leading to limited disclosure of memory or a restart.
Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
Sources
KEV status, EPSS score and vendor data refreshed automatically, last on 12 Oct 2026.