SB2026091584 - Remote denial of service in NGINX

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Main Vulnerability Database SB2026091584

SB2026091584 - Remote denial of service in NGINX

Published: September 15, 2026

Security Bulletin ID SB2026091584
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Remote access
Highest impact Data manipulation

Breakdown by Severity

Medium 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 vulnerability.


1) Heap-based buffer overflow (CVE-ID: CVE-2026-90439)

CWE-ID: CWE-122 - Heap-based Buffer Overflow

CVSSv4: 6.3 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to cause a denial of service or limited data corruption.

The vulnerability exists due to a heap-based buffer overflow in the ngx_http_v3_module module when processing a TLS handshake over HTTP/3. A remote attacker can initiate a TLS handshake to cause a denial of service or limited data corruption.

The issue occurs non-deterministically and is beyond the attacker\'s control. Only configurations using HTTP/3 with OpenSSL 3.5.0 or earlier are affected.


Remediation

Install update from vendor's website.

References