CVE-2026-42530

Public on 2026-06-17
Modified on 2026-06-20
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.
Severity
Important severity
Important
See what this means
CVSS v3 Base Score
8.1
See breakdown

Affected Packages

Platform Package Release Date Advisory Status
Amazon Linux 2 - Nginx1 Extra nginx Not Affected
Amazon Linux 2 - Nginx1.12 Extra nginx No Fix Planned
Amazon Linux 2023 nginx Not Affected
Amazon Linux 2023 nginx-mod-headers-more Not Affected

CVSS Scores

Score Type Score Vector
Amazon Linux CVSSv3 8.1 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H