Bug 2489872 (CVE-2026-42530)

Summary: CVE-2026-42530 nginx: ngx_http_v3_module: use-after-free issue leads to denial of service
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedCC: kaycoth, rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in the ngx_http_v3_module module of NGINX. When NGINX is configured to use the HTTP/3 QUIC module, an attacker can use a specially crafted HTTP/3 session to reopen a QPACK encoder stream and cause a use-after-free issue, potentially allowing code execution or a denial of service by forcing the process to restart.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-06-17 16:02:29 UTC
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.