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CVE-2021-21409

Possible request smuggling in HTTP/2 due missing validation of content-length

Published: Mar 30, 2021Updated: Nov 21, 2024 Sources: CVE List NVD GHSA BDUCWE-444
NVD MITRE
5.9CVSSMEDIUM
EPSS Score
4.9%
Top 9.0%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available

Description

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 4.1.61.Final there is a vulnerability that enables request smuggling. The content-length header is not correctly validated if the request only uses a single Http2HeaderFrame with the endStream set to to true. This could lead to request smuggling if the request is proxied to a remote peer and translated to HTTP/1.1. This is a followup of GHSA-wm47-8v5p-wjpj/CVE-2021-21295 which did miss to fix this one case. This was fixed as part of 4.1.61.Final.

CVSS Vector Breakdown

AV:NAC:HPR:NUI:NS:UC:NI:HA:N
Exploitability
AV:NAttack Vector
Network
AC:HAttack Complexity
High
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:HIntegrity
High
A:NAvailability
None
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Weaknesses

CWE-444

Affected Products

nettynetty
LibraryLibrary
OSS Libraries / generic-library
debian linuxdebian
On-premOS
Operating Systems / linux-distro
oncommand api servicesnetappHardware Firmware
oncommand workflow automationnetappHardware Firmware
banking corporate lending process managementoracle
On-premWeb App
Enterprise Software / itsm-monitoring
nettyoss-projectOSS Librariesaka io.netty:netty, netty-incubator-codec-ohttp
debianoss-projectGBOperating Systemsaka debian gnu/linux
netappcommercialUSHardware Firmware
oraclecommercialUSDatabasesaka oracle corp.
and 22 more affected products View all →

Attack Graph

Products CVE Techniques Tactics

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Exploitability

Official Patch Available

MITRE ATT&CK

1 technique
Collection
View detailed technique mapping

References

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-21295
cve.mitre.org
https://github.com/netty/netty/commit/b0fa4d5aab4215f3c22ce6123dd8dd5f38dc0432
github.com
https://github.com/netty/netty/security/advisories/GHSA-f256-j965-7f32
github.com
and 115 more references View all →

Timeline

Published
Mar 30, 2021
Last Updated
Nov 21, 2024

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