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Bug 817893 (CVE-2021-41136) - <www-servers/puma-5.5.2: request smuggling with Apache Airflow (CVE-2021-41136)
Summary: <www-servers/puma-5.5.2: request smuggling with Apache Airflow (CVE-2021-41136)
Alias: CVE-2021-41136
Product: Gentoo Security
Classification: Unclassified
Component: Vulnerabilities (show other bugs)
Hardware: All Linux
: Normal minor (vote)
Assignee: Gentoo Security
Whiteboard: C3 [glsa+]
Depends on: 821892
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Reported: 2021-10-12 19:35 UTC by John Helmert III
Modified: 2022-08-14 21:44 UTC (History)
1 user (show)

See Also:
Package list:
Runtime testing required: ---


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Description John Helmert III archtester Gentoo Infrastructure gentoo-dev Security 2021-10-12 19:35:48 UTC

Puma is a HTTP 1.1 server for Ruby/Rack applications. Prior to versions 5.5.1 and 4.3.9, using `puma` with a proxy which forwards HTTP header values which contain the LF character could allow HTTP request smugggling. A client could smuggle a request through a proxy, causing the proxy to send a response back to another unknown client. The only proxy which has this behavior, as far as the Puma team is aware of, is Apache Traffic Server. If the proxy uses persistent connections and the client adds another request in via HTTP pipelining, the proxy may mistake it as the first request's body. Puma, however, would see it as two requests, and when processing the second request, send back a response that the proxy does not expect. If the proxy has reused the persistent connection to Puma to send another request for a different client, the second response from the first client will be sent to the second client. This vulnerability was patched in Puma 5.5.1 and 4.3.9. As a workaround, do not use Apache Traffic Server with `puma`.

Fix in 5.5.1, please bump.
Comment 1 Hans de Graaff gentoo-dev 2022-02-12 07:24:58 UTC
Puma 5.5.2 has been added and marked stable.
Comment 2 John Helmert III archtester Gentoo Infrastructure gentoo-dev Security 2022-08-14 05:05:17 UTC
GLSA request filed
Comment 3 Larry the Git Cow gentoo-dev 2022-08-14 21:43:36 UTC
The bug has been referenced in the following commit(s):

commit 74f54f14d9074878f0b2b711ab3064799b15e9cb
Author:     GLSAMaker <>
AuthorDate: 2022-08-14 21:41:58 +0000
Commit:     Sam James <>
CommitDate: 2022-08-14 21:43:20 +0000

    [ GLSA 202208-28 ] Puma: Multiple Vulnerabilities
    Signed-off-by: GLSAMaker <>
    Signed-off-by: Sam James <>

 glsa-202208-28.xml | 48 ++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 48 insertions(+)
Comment 4 Sam James archtester Gentoo Infrastructure gentoo-dev Security 2022-08-14 21:44:03 UTC
GLSA done, all done.