CVE-2026-50020

MEDIUM EPSS 14.0%
Published Jun 12, 20262w ago · Modified Jun 17, 20261w ago
5.3 CVSS 3.1
Medium
Find Similar
Published Jun 12, 2026 2w ago
Last Modified Jun 17, 2026 1w ago

Description

Netty is a network application framework for development of protocol servers and clients. Prior to versions 4.1.135.Final and 4.2.15.Final, before reading the first request-line, `HttpObjectDecoder` skips every byte for which `Character.isISOControl(b)` is `true` (0x00–0x1F and 0x7F) as well as all whitespace. RFC 9112 §2.2 only asks servers to ignore empty CRLF lines preceding the request-line — a carefully scoped robustness allowance intended to handle HTTP/1.0 POST workarounds. Silently absorbing NUL bytes, SOH, STX, and other non-CRLF control characters goes significantly beyond this, and can be exploited for request-boundary confusion in pipelined or multiplexed transports where a front-end component treats those bytes differently. Versions 4.1.135.Final and 4.2.15.Final patch the issue.

CVSS Details

Base Score
5.3
Exploitability
3.9
Impact
1.4
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality None
Integrity Low
Availability None

Threat Intelligence

EPSS Exploit Probability
14.0% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available

Weaknesses 1

CWE-444

Affected Products 2

VendorProductVersionRange
nettynetty* <4.1.135
nettynetty*≥4.2.0  –  <4.2.15

References 3

  • github.com https://github.com/netty/netty/releases/tag/netty-4.1.135.Final
    Release Notes
  • github.com https://github.com/netty/netty/releases/tag/netty-4.2.15.Final
    Release Notes
  • github.com https://github.com/netty/netty/security/advisories/GHSA-hvcg-qmg6-jm4c
    Vendor Advisory

Remediation

No remediation data recorded yet

Check vendor advisories and the NVD entry for patch availability.