Use After Free Affecting nginx package, versions [1.31.0,1.31.2)
Threat Intelligence
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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Test your applications- Snyk IDSNYK-UNMANAGED-NGINX-17660905
- published28 Jun 2026
- disclosed17 Jun 2026
- creditUnknown
Introduced: 17 Jun 2026
CVE-2026-42530 (opens in a new tab)How to fix?
Upgrade nginx to version 1.31.2 or higher.
Overview
Affected versions of this package are vulnerable to Use After Free in the ngx_http_v3_module process when configured to use the HTTP/3 QUIC module. An attacker can cause the worker process to restart or potentially execute arbitrary code by sending a specially crafted HTTP/3 session that reopens a QPACK encoder stream. This is only exploitable if the HTTP/3 QUIC module is enabled in the configuration.
Workaround
This vulnerability can be mitigated by disabling HTTP/3 by removing quic from all listen directives.