cbcvebase.
CVE-2021-21295
published 2021-03-09

CVE-2021-21295: Netty is an open-source, asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers &…

PriorityP347medium5.9CVSS 3.1
AVNACHPRNUINSUCNIHAN
EPSS
18.89%
96.9th percentile
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`.

Affected

45 ranges· showing 25
VendorProductVersion rangeFixed in
apachekudu< 1.16.01.16.0
apachezookeeper
debiandebian_linux
debiannetty< netty 1:4.1.48-3 (bookworm)netty 1:4.1.48-3 (bookworm)
debiannetty< netty 1:4.1.48-4 (bookworm)netty 1:4.1.48-4 (bookworm)
nettynetty< 4.1.61.Final4.1.61.Final
nettynetty< 4.1.614.1.61
nettynetty< 4.1.604.1.60
nettynetty>= 0 < 1:4.1.48-31:4.1.48-3
nettynetty>= 0 < 1:4.1.48-41:4.1.48-4
nettynetty>= 0 < 1:4.1.48-31:4.1.48-3
nettynetty>= 0 < 1:4.1.48-41:4.1.48-4
nettynetty>= 0 < 1:4.1.48-31:4.1.48-3
nettynetty>= 0 < 1:4.1.48-41:4.1.48-4
nettynetty>= 0 < 1:4.1.48-31:4.1.48-3
nettynetty>= 0 < 1:4.1.48-41:4.1.48-4
nettynetty>= 0 < 1:4.1.48-4+deb11u1build0.22.04.11:4.1.48-4+deb11u1build0.22.04.1
nettynetty>= 0 < 1:4.0.34-1ubuntu0.1~esm11:4.0.34-1ubuntu0.1~esm1
nettynetty>= 0 < 1:4.1.7-4ubuntu0.1+esm21:4.1.7-4ubuntu0.1+esm2
nettynetty>= 0 < 1:4.1.45-1ubuntu0.1~esm11:4.1.45-1ubuntu0.1~esm1
oraclebanking_corporate_lending_process_management
oraclebanking_corporate_lending_process_management
oraclebanking_corporate_lending_process_management
oraclebanking_credit_facilities_process_management
oraclebanking_credit_facilities_process_management

CVSS provenance

nvdv3.15.9MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
nvdv2.02.6LOWAV:N/AC:H/Au:N/C:N/I:P/A:N
osv7.5HIGH
vendor_ubuntu7.5HIGH
vendor_debian5.9MEDIUM
vendor_oracle5.9MEDIUM
vendor_redhat5.9MEDIUM
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