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`.
Published: 2021-03-09
Score: 5.9 Medium
EPSS: < 1% Very Low
KEV: No
Impact: n/a
Action: n/a
AI Analysis

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Remediation

No vendor fix or workaround currently provided.

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Tracking

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Advisories
Source ID Title
Debian DSA Debian DSA DSA-4885-1 netty security update
EUVD EUVD EUVD-2021-0719 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`.
Github GHSA Github GHSA GHSA-wm47-8v5p-wjpj Possible request smuggling in HTTP/2 due missing validation
Ubuntu USN Ubuntu USN USN-6049-1 Netty vulnerabilities
References
Link Providers
https://github.com/Netflix/zuul/pull/980 cve-icon cve-icon
https://github.com/netty/netty/commit/89c241e3b1795ff257af4ad6eadc616cb2fb3dc4 cve-icon cve-icon
https://github.com/netty/netty/security/advisories/GHSA-wm47-8v5p-wjpj cve-icon cve-icon cve-icon
https://lists.apache.org/thread.html/r02e467123d45006a1dda20a38349e9c74c3a4b53e2e07be0939ecb3f%40%3Cdev.ranger.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r040a5e4d9cca2f98354b58a70b27099672276f66995c4e2e39545d0b%40%3Cissues.hbase.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r04a3e0d9f53421fb946c60cc54762b7151dc692eb4e39970a7579052%40%3Ccommits.servicecomb.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r0b09f3e31e004fe583f677f7afa46bd30110904576c13c5ac818ac2c%40%3Cissues.flink.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r15f66ada9a5faf4bac69d9e7c4521cedfefa62df9509881603791969%40%3Cjira.kafka.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r16c4b55ac82be72f28adad4f8061477e5f978199d5725691dcc82c24%40%3Ccommits.servicecomb.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r1908a34b9cc7120e5c19968a116ddbcffea5e9deb76c2be4fa461904%40%3Cdev.zookeeper.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r1bca0b81193b74a451fc6d687ab58ef3a1f5ec40f6c61561d8dd9509%40%3Cissues.zookeeper.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r22adb45fe902aeafcd0a1c4db13984224a667676c323c66db3af38a1%40%3Ccommits.zookeeper.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r22b2f34447d71c9a0ad9079b7860323d5584fb9b40eb42668c21eaf1%40%3Cissues.hbase.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r268850f26639ebe249356ed6d8edb54ee8943be6f200f770784fb190%40%3Cissues.hbase.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r27b7e5a588ec826b15f38c40be500c50073400019ce7b8adfd07fece%40%3Cissues.hbase.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r2936730ef0a06e724b96539bc7eacfcd3628987c16b1b99c790e7b87%40%3Cissues.zookeeper.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r2e93ce23e04c3f0a61e987d1111d0695cb668ac4ec4edbf237bd3e80%40%3Ccommits.servicecomb.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r312ce5bd3c6bf08c138349b507b6f1c25fe9cf40b6f2b0014c9d12b1%40%3Cnotifications.zookeeper.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r32b0b640ad2be3b858f0af51c68a7d5c5a66a462c8bbb93699825cd3%40%3Cissues.zookeeper.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r33eb06b05afbc7df28d31055cae0cb3fd36cab808c884bf6d680bea5%40%3Cdev.zookeeper.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r393a339ab0b63ef9e6502253eeab26e7643b3e69738d5948b2b1d064%40%3Cissues.hbase.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r3c293431c781696681abbfe1c573c2d9dcdae6fd3ff330ea22f0433f%40%3Cjira.kafka.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r3c4596b9b37f5ae91628ccf169d33cd5a0da4b16b6c39d5bad8e03f3%40%3Cdev.jackrabbit.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r3ff9e735ca33612d900607dc139ebd38a64cadc6bce292e53eb86d7f%40%3Cissues.zookeeper.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r490ca5611c150d193b320a2608209180713b7c68e501b67b0cffb925%40%3Ccommits.servicecomb.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r4ea2f1a9d79d4fc1896e085f31fb60a21b1770d0a26a5250f849372d%40%3Cissues.kudu.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r5232e33a1f3b310a3e083423f736f3925ebdb150844d60ac582809f8%40%3Cnotifications.zookeeper.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r5470456cf1409a99893ae9dd57439799f6dc1a60fda90e11570f66fe%40%3Cnotifications.zookeeper.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r57245853c7245baab09eae08728c52b58fd77666538092389cc3e882%40%3Ccommits.servicecomb.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r584cf871f188c406d8bd447ff4e2fd9817fca862436c064d0951a071%40%3Ccommits.pulsar.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r59bac5c09f7a4179b9e2460e8f41c278aaf3b9a21cc23678eb893e41%40%3Cjira.kafka.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r5baac01f9e06c40ff7aab209d5751b3b58802c63734e33324b70a06a%40%3Cissues.flink.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r5e66e286afb5506cdfe9bbf68a323e8d09614f6d1ddc806ed0224700%40%3Cjira.kafka.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r5fc5786cdd640b1b0a3c643237ce0011f0a08a296b11c0e2c669022c%40%3Cdev.kafka.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r602e98daacc98934f097f07f2eed6eb07c18bfc1949c8489dc7bfcf5%40%3Cissues.flink.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r67c4f90658fde875521c949448c54c98517beecdc7f618f902c620ec%40%3Cissues.zookeeper.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r67e6a636cbc1958383a1cd72b7fd0cd7493360b1dd0e6c12f5761798%40%3Cnotifications.zookeeper.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r6a122c25e352eb134d01e7f4fc4d345a491c5ee9453fef6fc754d15b%40%3Ccommits.zookeeper.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r6a29316d758db628a1df49ca219d64caf493999b52cc77847bfba675%40%3Cnotifications.zookeeper.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r6aee7e3566cb3e51eeed2fd8786704d91f80a7581e00a787ba9f37f6%40%3Cissues.hbase.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r6d32fc3cd547f7c9a288a57c7f525f5d00a00d5d163613e0d10a23ef%40%3Ccommits.servicecomb.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r70cebada51bc6d49138272437d8a28fe971d0197334ef906b575044c%40%3Ccommits.zookeeper.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r790c2926efcd062067eb18fde2486527596d7275381cfaff2f7b3890%40%3Cissues.bookkeeper.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r7bb3cdc192e9a6f863d3ea05422f09fa1ae2b88d4663e63696ee7ef5%40%3Cdev.ranger.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r837bbcbf12e335e83ab448b1bd2c1ad7e86efdc14034b23811422e6a%40%3Ccommits.zookeeper.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r855b4b6814ac829ce2d48dd9d8138d07f33387e710de798ee92c011e%40%3Cissues.flink.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r86cd38a825ab2344f3e6cad570528852f29a4ffdf56ab67d75c36edf%40%3Cissues.hbase.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r8bcaf7821247b1836b10f6a1a3a3212b06272fd4cde4a859de1b78cf%40%3Ccommits.servicecomb.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r8db1d7b3b9acc9e8d2776395e280eb9615dd7790e1da8c57039963de%40%3Cnotifications.zookeeper.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r9051e4f484a970b5566dc1870ecd9c1eb435214e2652cf3ea4d0c0cc%40%3Cjira.kafka.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r905b92099998291956eebf4f1c5d95f5a0cbcece2946cc46d32274fd%40%3Cdev.hbase.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r96ce18044880c33634c4b3fcecc57b8b90673c9364d63eba00385523%40%3Cjira.kafka.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/r9924ef9357537722b28d04c98a189750b80694a19754e5057c34ca48%40%3Ccommits.pulsar.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/ra64d56a8a331ffd7bdcd24a9aaaeeedeacd5d639f5a683389123f898%40%3Cdev.flink.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/ra655e5cec74d1ddf62adacb71d398abd96f3ea2c588f6bbf048348eb%40%3Cissues.kudu.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/ra83096bcbfe6e1f4d54449f8a013117a0536404e9d307ab4a0d34f81%40%3Cissues.hbase.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/ra96c74c37ed7252f78392e1ad16442bd16ae72a4d6c8db50dd55c88b%40%3Ccommits.servicecomb.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/racc191a1f70a4f13155e8002c61bddef2870b26441971c697436ad5d%40%3Ccommits.servicecomb.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/rae198f44c3f7ac5264045e6ba976be1703cff38dcf1609916e50210d%40%3Ccommits.servicecomb.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/rb06c1e766aa45ee422e8261a8249b561784186483e8f742ea627bda4%40%3Cdev.kafka.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/rb51d6202ff1a773f96eaa694b7da4ad3f44922c40b3d4e1a19c2f325%40%3Ccommits.pulsar.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/rb523bb6c60196c5f58514b86a8585c2069a4852039b45de3818b29d2%40%3Ccommits.servicecomb.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/rb592033a2462548d061a83ac9449c5ff66098751748fcd1e2d008233%40%3Cissues.zookeeper.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/rb95d42ce220ed4a4683aa17833b5006d657bc4254bc5cb03cd5e6bfb%40%3Cissues.hbase.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/rbadcbcb50195f00bbd196403865ced521ca70787999583c07be38d0e%40%3Cnotifications.zookeeper.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/rbed09768f496244a2e138dbbe6d2847ddf796c9c8ef9e50f2e3e30d9%40%3Cnotifications.zookeeper.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/rc0087125cb15b4b78e44000f841cd37fefedfda942fd7ddf3ad1b528%40%3Cissues.zookeeper.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/rc165e36ca7cb5417aec3f21bbc4ec00fb38ecebdd96a82cfab9bd56f%40%3Cjira.kafka.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/rc73b8dd01b1be276d06bdf07883ecd93fe1a01f139a99ef30ba4308c%40%3Ccommits.servicecomb.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/rca0978b634a0c3ebee4126ec29c7f570b165fae3f8f3658754c1cbd3%40%3Cissues.kudu.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/rcd163e421273e8dca1c71ea298dce3dd11b41d51c3a812e0394e6a5d%40%3Ccommits.pulsar.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/rcf3752209a8b04996373bf57fdc808b3bfaa2be8702698a0323641f8%40%3Ccommits.hbase.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/rcfc154eb2de23d2dc08a56100341161e1a40a8ea86c693735437e8f2%40%3Ccommits.servicecomb.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/rcfc535afd413d9934d6ee509dce234dac41fa3747a7555befb17447e%40%3Cissues.zookeeper.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/rd25c88aad0e76240dd09f0eb34bdab924933946429e068a167adcb73%40%3Ccommits.servicecomb.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/rd4a6b7dec38ea6cd28b6f94bd4b312629a52b80be3786d5fb0e474bc%40%3Cissues.kudu.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/rd8f72411fb75b98d366400ae789966373b5c3eb3f511e717caf3e49e%40%3Cissues.flink.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/rdb4db3f5a9c478ca52a7b164680b88877a5a9c174e7047676c006b2c%40%3Ccommits.servicecomb.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/rdc096e13ac4501ea2e2b03a197682a313b85d3d3ec89d5ae5551b384%40%3Cissues.zookeeper.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/rddbb4f8d5db23265bb63d14ef4b3723b438abc1589f877db11d35450%40%3Cissues.zookeeper.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/re4f70b62843e92163fab03b65e2aa8078693293a0c36f1cc260079ed%40%3Ccommits.servicecomb.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/re6207ebe2ca4d44f2a6deee695ad6f27fd29d78980f1d46ed1574f91%40%3Cissues.zookeeper.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/re7c69756a102bebce8b8681882844a53e2f23975a189363e68ad0324%40%3Cissues.flink.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/reafc834062486adfc7be5bb8f7b7793be0d33f483678a094c3f9d468%40%3Ccommits.servicecomb.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/rf36f1114e84a3379b20587063686148e2d5a39abc0b8a66ff2a9087a%40%3Cissues.zookeeper.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/rf87b870a22aa5c77c27900967b518a71a7d954c2952860fce3794b60%40%3Ccommits.servicecomb.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/rf934292a4a1c189827f625d567838d2c1001e4739b158638d844105b%40%3Cissues.kudu.apache.org%3E cve-icon cve-icon
https://lists.apache.org/thread.html/rfff6ff8ffb31e8a32619c79774def44b6ffbb037c128c5ad3eab7171%40%3Cissues.zookeeper.apache.org%3E cve-icon cve-icon
https://nvd.nist.gov/vuln/detail/CVE-2021-21295 cve-icon
https://security.netapp.com/advisory/ntap-20210604-0003/ cve-icon cve-icon
https://www.cve.org/CVERecord?id=CVE-2021-21295 cve-icon
https://www.debian.org/security/2021/dsa-4885 cve-icon cve-icon
https://www.oracle.com/security-alerts/cpuapr2022.html cve-icon cve-icon
History

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Apache Kudu Zookeeper
Debian Debian Linux
Netapp Oncommand Api Services Oncommand Workflow Automation
Netty Netty
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cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2024-08-03T18:09:15.344Z

Reserved: 2020-12-22T00:00:00.000Z

Link: CVE-2021-21295

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Modified

Published: 2021-03-09T19:15:12.657

Modified: 2024-11-21T05:47:57.530

Link: CVE-2021-21295

cve-icon Redhat

Severity : Moderate

Publid Date: 2021-03-09T00:00:00Z

Links: CVE-2021-21295 - Bugzilla

cve-icon OpenCVE Enrichment

No data.

Weaknesses