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SCA: security update for io.netty:netty-codec-http2 (GHSA-wm47-8v5p-wjpj)

medium Tenable Cloud Security Plugin ID 419988

Description

There are packages installed that are affected by a vulnerability referenced in the following CVE:

 - Netty is an open-source, asynchronous event-driven network application framework for rapid development of
 maintainable high performance protocol servers & clients. In Netty (io.netty:netty-codec-http2) before
 version 4.1.60.Final there is a vulnerability that enables request smuggling. If a Content-Length header
 is present in the original HTTP/2 request, the field is not validated by `Http2MultiplexHandler` as it is
 propagated up. This is fine as long as the request is not proxied through as HTTP/1.1. If the request
 comes in as an HTTP/2 stream, gets converted into the HTTP/1.1 domain objects (`HttpRequest`,
 `HttpContent`, etc.) via `Http2StreamFrameToHttpObjectCodec `and then sent up to the child channel's
 pipeline and proxied through a remote peer as HTTP/1.1 this may result in request smuggling. In a proxy
 case, users may assume the content-length is validated somehow, which is not the case. If the request is
 forwarded to a backend channel that is a HTTP/1.1 connection, the Content-Length now has meaning and needs
 to be checked. An attacker can smuggle requests inside the body as it gets downgraded from HTTP/2 to
 HTTP/1.1. For an example attack refer to the linked GitHub Advisory. Users are only affected if all of
 this is true: `HTTP2MultiplexCodec` or `Http2FrameCodec` is used, `Http2StreamFrameToHttpObjectCodec` is
 used to convert to HTTP/1.1 objects, and these HTTP/1.1 objects are forwarded to another remote peer. This
 has been patched in 4.1.60.Final As a workaround, the user can do the validation by themselves by
 implementing a custom `ChannelInboundHandler` that is put in the `ChannelPipeline` behind
 `Http2StreamFrameToHttpObjectCodec`. (CVE-2021-21295)

See Also

https://github.com/advisories/GHSA-wm47-8v5p-wjpj

Plugin Details

Severity: Medium

ID: 419988

Version: Revision 1.6

Type: Local

Family: SCA Checks

Published: 1/23/2025

Updated: 7/2/2026

Supported Sensors: Tenable Cloud Security, Tenable Self-Hosted Container Security

Risk Information

VPR

Risk Factor: Low

Score: 3

Percentile: 23.18

Vendor

Vendor Severity: Medium

CVSS v2

Risk Factor: Low

Base Score: 2.6

Temporal Score: 1.9

Vector: CVSS2#AV:N/AC:H/Au:N/C:N/I:P/A:N

CVSS Score Source: CVE-2021-21295

CVSS v3

Risk Factor: Medium

Base Score: 5.9

Temporal Score: 5.2

Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

Exploit Ease: No known exploits are available

Patch Publication Date: 3/9/2021

Vulnerability Publication Date: 3/9/2021

Reference Information

CVE: CVE-2021-21295

cwe: CWE-444