Unrated severityNVD Advisory· Published Jun 17, 2026· Updated Jun 18, 2026
NGINX Open-Source ngx_http_v3_module vulnerability
CVE-2026-42530
Description
NGINX Open Source has a vulnerability in the ngx_http_v3_module module. When NGINX Open Source is configured to use the HTTP/3 QUIC module, a remote unauthenticated attacker along with conditions beyond their control can use a specially crafted HTTP/3 session to reopen a QPACK encoder stream. This may cause a Use-after-Free 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.
Affected products
3- osv-coords3 versions
>= 1.31.0, < 1.31.2+ 2 more
- (no CPE)range: >= 1.31.0, < 1.31.2
- (no CPE)range: >= 1.31.0, < 1.31.2
- (no CPE)range: < 1.31.2-1.1
Patches
Vulnerability mechanics
References
1- my.f5.com/manage/s/article/K000161616mitrevendor-advisory
News mentions
6- Nginx Buffer Overflow Vulnerability Allows Attackers to Execute Arbitrary Code – PoC ReleasedCyber Security News · Jul 28, 2026
- Unpatched XRING Flaw in XQUIC Lets Remote Clients Crash HTTP/3 ServersThe Hacker News · Jul 10, 2026
- F5 Patches Two Critical NGINX Open Source Flaws Enabling Remote Code ExecutionThe Hacker News · Jun 18, 2026
- F5 Patches NGINX Vulnerability That Enables Code Execution and DoS AttacksCyber Security News · Jun 18, 2026
- F5 issues out-of-band patches for critical NGINX vulnerabilitiesBleepingComputer · Jun 18, 2026
- F5 Patches Critical, High-Severity NGINX VulnerabilitiesSecurityWeek · Jun 18, 2026