---
id: CVE-2026-12606
title: >-
  Eclipse Grizzly in versions before 5.0.2, cannot properly parse the trailer
  section in malformed trailer header's line, which can be leveraged to perform
  HTTP request smuggling
summary: >-
  Eclipse Grizzly in versions before 5.0.2, cannot properly parse the trailer
  section in malformed trailer header's line, which can be leveraged to perform
  HTTP request smuggling. Grizzly 5.0.1 supports system properties that enable
  the be…
severity: medium
cvss: 5.3
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N'
cwe:
  - CWE-444
vendor: eclipse
product: grizzly
affected:
  - 'grizzly >= 4.0.0, <= 4.0.2'
  - 'grizzly >= 5.0.0, < 5.0.2'
patched:
  - grizzly 5.0.2
published: '2026-07-14'
updated: '2026-07-27'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-12606'
references:
  - url: 'https://gitlab.eclipse.org/security/cve-assignment/-/work_items/129'
    label: emo@eclipse.org
tags:
  - nvd
epss: 0.00297
epssPercentile: 0.19955
ingestedAt: '2026-07-27T13:18:48.784Z'
---

## Overview

Eclipse Grizzly in versions before 5.0.2, cannot properly parse the trailer section in malformed trailer header's line, which can be leveraged to perform HTTP request smuggling. Grizzly 5.0.1 supports system properties that enable the behavior that fixes the vulnerability - set org.glassfish.grizzly.http.STRICT_HEADER_NAME_VALIDATION_RFC_9110 and org.glassfish.grizzly.http.STRICT_HEADER_VALUE_VALIDATION_RFC_9110 system properties to "true".

## Affected

- `grizzly >= 4.0.0, <= 4.0.2`
- `grizzly >= 5.0.0, < 5.0.2`

## Remediation

Upgrade past the affected range:

- `grizzly 5.0.2`