CVE-2026-42530
CRITICAL EPSS 81.9%
Published Jun 17, 20261w ago · Modified Jun 18, 20261w ago
9.2 CVSS 4.0
Published Jun 17, 2026 1w ago
Last Modified Jun 18, 2026 1w ago
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.
CVSS Details
Base Score
Exploitability
Impact
Vector string
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Attack Vector Network
Attack Complexity High
Privileges Required None
User Interaction None
Scope X
Threat Intelligence
EPSS Exploit Probability
81.9% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available
Weaknesses 1
CWE-416 Use After Free Memory Safety
References 1
- my.f5.com https://my.f5.com/manage/s/article/K000161616
Remediation
No remediation data recorded yet
Check vendor advisories and the NVD entry for patch availability.