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National Vulnerability Database

National Vulnerability Database

NVD

  1. Vulnerabilities

CVE-2021-21295 Detail

Current 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 4.1.60.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`.


View Analysis Description

Severity

 


CVSS 3.x Severity and Metrics:

NIST CVSS score matches with CNA score
CNA:  GitHub, Inc.
Base Score:  5.9 MEDIUM
Vector:  CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N


NVD Analysts use publicly available information to associate vector strings and CVSS scores. We also display any CVSS information provided within the CVE List from the CNA.

Note: The NVD and the CNA have provided the same score. When this occurs only the CNA information is displayed, but the Acceptance Level icon for the CNA is given a checkmark to signify NVD concurrence.

References to Advisories, Solutions, and Tools

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Hyperlink Resource
https://github.com/Netflix/zuul/pull/980 Patch  Third Party Advisory 
https://github.com/netty/netty/commit/89c241e3b1795ff257af4ad6eadc616cb2fb3dc4 Patch  Vendor Advisory 
https://github.com/netty/netty/security/advisories/GHSA-wm47-8v5p-wjpj Third Party Advisory 
https://lists.apache.org/thread.html/r02e467123d45006a1dda20a38349e9c74c3a4b53e2e07be0939ecb3f@%3Cdev.ranger.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r040a5e4d9cca2f98354b58a70b27099672276f66995c4e2e39545d0b@%3Cissues.hbase.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r04a3e0d9f53421fb946c60cc54762b7151dc692eb4e39970a7579052@%3Ccommits.servicecomb.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r0b09f3e31e004fe583f677f7afa46bd30110904576c13c5ac818ac2c@%3Cissues.flink.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r15f66ada9a5faf4bac69d9e7c4521cedfefa62df9509881603791969@%3Cjira.kafka.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r16c4b55ac82be72f28adad4f8061477e5f978199d5725691dcc82c24@%3Ccommits.servicecomb.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r1908a34b9cc7120e5c19968a116ddbcffea5e9deb76c2be4fa461904@%3Cdev.zookeeper.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r1bca0b81193b74a451fc6d687ab58ef3a1f5ec40f6c61561d8dd9509@%3Cissues.zookeeper.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r22adb45fe902aeafcd0a1c4db13984224a667676c323c66db3af38a1@%3Ccommits.zookeeper.apache.org%3E Mailing List  Patch  Third Party Advisory 
https://lists.apache.org/thread.html/r22b2f34447d71c9a0ad9079b7860323d5584fb9b40eb42668c21eaf1@%3Cissues.hbase.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r268850f26639ebe249356ed6d8edb54ee8943be6f200f770784fb190@%3Cissues.hbase.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r27b7e5a588ec826b15f38c40be500c50073400019ce7b8adfd07fece@%3Cissues.hbase.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r2936730ef0a06e724b96539bc7eacfcd3628987c16b1b99c790e7b87@%3Cissues.zookeeper.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r2e93ce23e04c3f0a61e987d1111d0695cb668ac4ec4edbf237bd3e80@%3Ccommits.servicecomb.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r312ce5bd3c6bf08c138349b507b6f1c25fe9cf40b6f2b0014c9d12b1@%3Cnotifications.zookeeper.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r32b0b640ad2be3b858f0af51c68a7d5c5a66a462c8bbb93699825cd3@%3Cissues.zookeeper.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r33eb06b05afbc7df28d31055cae0cb3fd36cab808c884bf6d680bea5@%3Cdev.zookeeper.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r393a339ab0b63ef9e6502253eeab26e7643b3e69738d5948b2b1d064@%3Cissues.hbase.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r3c293431c781696681abbfe1c573c2d9dcdae6fd3ff330ea22f0433f@%3Cjira.kafka.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r3c4596b9b37f5ae91628ccf169d33cd5a0da4b16b6c39d5bad8e03f3@%3Cdev.jackrabbit.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r3ff9e735ca33612d900607dc139ebd38a64cadc6bce292e53eb86d7f@%3Cissues.zookeeper.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r490ca5611c150d193b320a2608209180713b7c68e501b67b0cffb925@%3Ccommits.servicecomb.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r4ea2f1a9d79d4fc1896e085f31fb60a21b1770d0a26a5250f849372d@%3Cissues.kudu.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r5232e33a1f3b310a3e083423f736f3925ebdb150844d60ac582809f8@%3Cnotifications.zookeeper.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r5470456cf1409a99893ae9dd57439799f6dc1a60fda90e11570f66fe@%3Cnotifications.zookeeper.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r57245853c7245baab09eae08728c52b58fd77666538092389cc3e882@%3Ccommits.servicecomb.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r584cf871f188c406d8bd447ff4e2fd9817fca862436c064d0951a071@%3Ccommits.pulsar.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r59bac5c09f7a4179b9e2460e8f41c278aaf3b9a21cc23678eb893e41@%3Cjira.kafka.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r5baac01f9e06c40ff7aab209d5751b3b58802c63734e33324b70a06a@%3Cissues.flink.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r5e66e286afb5506cdfe9bbf68a323e8d09614f6d1ddc806ed0224700@%3Cjira.kafka.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r5fc5786cdd640b1b0a3c643237ce0011f0a08a296b11c0e2c669022c@%3Cdev.kafka.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r602e98daacc98934f097f07f2eed6eb07c18bfc1949c8489dc7bfcf5@%3Cissues.flink.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r67c4f90658fde875521c949448c54c98517beecdc7f618f902c620ec@%3Cissues.zookeeper.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r67e6a636cbc1958383a1cd72b7fd0cd7493360b1dd0e6c12f5761798@%3Cnotifications.zookeeper.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r6a122c25e352eb134d01e7f4fc4d345a491c5ee9453fef6fc754d15b@%3Ccommits.zookeeper.apache.org%3E Mailing List  Patch  Third Party Advisory 
https://lists.apache.org/thread.html/r6a29316d758db628a1df49ca219d64caf493999b52cc77847bfba675@%3Cnotifications.zookeeper.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r6aee7e3566cb3e51eeed2fd8786704d91f80a7581e00a787ba9f37f6@%3Cissues.hbase.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r6d32fc3cd547f7c9a288a57c7f525f5d00a00d5d163613e0d10a23ef@%3Ccommits.servicecomb.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r70cebada51bc6d49138272437d8a28fe971d0197334ef906b575044c@%3Ccommits.zookeeper.apache.org%3E Mailing List  Patch  Third Party Advisory 
https://lists.apache.org/thread.html/r790c2926efcd062067eb18fde2486527596d7275381cfaff2f7b3890@%3Cissues.bookkeeper.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r7bb3cdc192e9a6f863d3ea05422f09fa1ae2b88d4663e63696ee7ef5@%3Cdev.ranger.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r837bbcbf12e335e83ab448b1bd2c1ad7e86efdc14034b23811422e6a@%3Ccommits.zookeeper.apache.org%3E Mailing List  Patch  Third Party Advisory 
https://lists.apache.org/thread.html/r855b4b6814ac829ce2d48dd9d8138d07f33387e710de798ee92c011e@%3Cissues.flink.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r86cd38a825ab2344f3e6cad570528852f29a4ffdf56ab67d75c36edf@%3Cissues.hbase.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r8bcaf7821247b1836b10f6a1a3a3212b06272fd4cde4a859de1b78cf@%3Ccommits.servicecomb.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r8db1d7b3b9acc9e8d2776395e280eb9615dd7790e1da8c57039963de@%3Cnotifications.zookeeper.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r9051e4f484a970b5566dc1870ecd9c1eb435214e2652cf3ea4d0c0cc@%3Cjira.kafka.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r905b92099998291956eebf4f1c5d95f5a0cbcece2946cc46d32274fd@%3Cdev.hbase.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r96ce18044880c33634c4b3fcecc57b8b90673c9364d63eba00385523@%3Cjira.kafka.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r9924ef9357537722b28d04c98a189750b80694a19754e5057c34ca48@%3Ccommits.pulsar.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/ra64d56a8a331ffd7bdcd24a9aaaeeedeacd5d639f5a683389123f898@%3Cdev.flink.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/ra655e5cec74d1ddf62adacb71d398abd96f3ea2c588f6bbf048348eb@%3Cissues.kudu.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/ra83096bcbfe6e1f4d54449f8a013117a0536404e9d307ab4a0d34f81@%3Cissues.hbase.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/ra96c74c37ed7252f78392e1ad16442bd16ae72a4d6c8db50dd55c88b@%3Ccommits.servicecomb.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/racc191a1f70a4f13155e8002c61bddef2870b26441971c697436ad5d@%3Ccommits.servicecomb.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/rae198f44c3f7ac5264045e6ba976be1703cff38dcf1609916e50210d@%3Ccommits.servicecomb.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/rb06c1e766aa45ee422e8261a8249b561784186483e8f742ea627bda4@%3Cdev.kafka.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/rb51d6202ff1a773f96eaa694b7da4ad3f44922c40b3d4e1a19c2f325@%3Ccommits.pulsar.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/rb523bb6c60196c5f58514b86a8585c2069a4852039b45de3818b29d2@%3Ccommits.servicecomb.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/rb592033a2462548d061a83ac9449c5ff66098751748fcd1e2d008233@%3Cissues.zookeeper.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/rb95d42ce220ed4a4683aa17833b5006d657bc4254bc5cb03cd5e6bfb@%3Cissues.hbase.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/rbadcbcb50195f00bbd196403865ced521ca70787999583c07be38d0e@%3Cnotifications.zookeeper.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/rbed09768f496244a2e138dbbe6d2847ddf796c9c8ef9e50f2e3e30d9@%3Cnotifications.zookeeper.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/rc0087125cb15b4b78e44000f841cd37fefedfda942fd7ddf3ad1b528@%3Cissues.zookeeper.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/rc165e36ca7cb5417aec3f21bbc4ec00fb38ecebdd96a82cfab9bd56f@%3Cjira.kafka.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/rc73b8dd01b1be276d06bdf07883ecd93fe1a01f139a99ef30ba4308c@%3Ccommits.servicecomb.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/rca0978b634a0c3ebee4126ec29c7f570b165fae3f8f3658754c1cbd3@%3Cissues.kudu.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/rcd163e421273e8dca1c71ea298dce3dd11b41d51c3a812e0394e6a5d@%3Ccommits.pulsar.apache.org%3E Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/rcf3752209a8b04996373bf57fdc808b3bfaa2be8702698a0323641f8@%3Ccommits.hbase.apache.org%3E Mailing List  Patch  Third Party Advisory 
https://lists.apache.org/thread.html/rcfc154eb2de23d2dc08a56100341161e1a40a8ea86c693735437e8f2@%3Ccommits.servicecomb.apache.org%3E Mailing List  Third Party Advisory 
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https://lists.apache.org/thread.html/rdc096e13ac4501ea2e2b03a197682a313b85d3d3ec89d5ae5551b384@%3Cissues.zookeeper.apache.org%3E Mailing List  Third Party Advisory 
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https://lists.apache.org/thread.html/re6207ebe2ca4d44f2a6deee695ad6f27fd29d78980f1d46ed1574f91@%3Cissues.zookeeper.apache.org%3E Mailing List  Third Party Advisory 
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https://security.netapp.com/advisory/ntap-20210604-0003/ Third Party Advisory 
https://www.debian.org/security/2021/dsa-4885 Third Party Advisory 

Weakness Enumeration

CWE-ID CWE Name Source
CWE-444 Inconsistent Interpretation of HTTP Requests ('HTTP Request Smuggling') cwe source acceptance level NIST   Provider acceptance level GitHub, Inc.  

Known Affected Software Configurations Switch to CPE 2.2

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Denotes Vulnerable Software
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Change History

51 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2021-21295
NVD Published Date:
03/09/2021
NVD Last Modified:
12/09/2021
Source:
GitHub, Inc.