SB2026032533 - Multiple vulnerabilities in Netty

Description

This security bulletin contains information about 2 secuirty vulnerabilities.

1) Inconsistent interpretation of HTTP requests (CVE-ID: CVE-2026-33870)

The vulnerability allows a remote attacker to perform HTTP request smuggling attacks.

The vulnerability exists due to improper validation of HTTP requests within chunked transfer encoding extension values. A remote attacker can send a specially crafted HTTP request to the server and smuggle arbitrary HTTP headers.

2) Allocation of Resources Without Limits or Throttling (CVE-ID: CVE-2026-33871)

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to allocation of resources without limits or throttling in the "DefaultHttp2FrameReader" function within HTTP/2 server. A remote attacker can send a flood of CONTINUATION frames and cause a denial of service condition on the target system.

Remediation

Install update from vendor's website.

References

• https://github.com/netty/netty/security/advisories/GHSA-pwqr-wmgm-9rr8
• https://github.com/netty/netty/security/advisories/GHSA-w9fj-cfpg-grvv