cbcvebase.
CVE-2019-16770
published 2021-05-11

CVE-2019-16770: Puma is a concurrent HTTP 1.1 server for Ruby/Rack applications. The fix for CVE-2019-16770 was incomplete. The original fix only protected existing…

PriorityP340high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
1.96%
78.1th percentile
Puma is a concurrent HTTP 1.1 server for Ruby/Rack applications. The fix for CVE-2019-16770 was incomplete. The original fix only protected existing connections that had already been accepted from having their requests starved by greedy persistent-connections saturating all threads in the same process. However, new connections may still be starved by greedy persistent-connections saturating all threads in all processes in the cluster. A `puma` server which received more concurrent `keep-alive` connections than the server had threads in its threadpool would service only a subset of connections, denying service to the unserved connections. This problem has been fixed in `puma` 4.3.8 and 5.3.1. Setting `queue_requests false` also fixes the issue. This is not advised when using `puma` without a reverse proxy, such as `nginx` or `apache`, because you will open yourself to slow client attacks (e.g. slowloris). The fix is very small and a git patch is available for those using unsupported versions of Puma.

Affected

22 ranges
VendorProductVersion rangeFixed in
debiandebian_linux
debiandebian_linux
debianpuma< puma 4.3.8-1 (bookworm)puma 4.3.8-1 (bookworm)
debianpuma< puma 3.12.0-4 (bookworm)puma 3.12.0-4 (bookworm)
pumapuma< 4.3.84.3.8
pumapuma< 4.3.84.3.8
pumapuma
pumapuma>= 0 < 3.12.0-43.12.0-4
pumapuma>= 0 < 4.3.8-14.3.8-1
pumapuma>= 0 < 3.12.0-43.12.0-4
pumapuma>= 0 < 4.3.8-14.3.8-1
pumapuma>= 0 < 3.12.0-43.12.0-4
pumapuma>= 0 < 4.3.8-14.3.8-1
pumapuma>= 0 < 3.12.0-43.12.0-4
pumapuma>= 0 < 4.3.8-14.3.8-1
pumapuma>= 0 < 4.3.84.3.8
pumapuma>= 0 < 3.12.23.12.2
pumapuma>= 3.0.0 < 3.12.23.12.2
pumapuma>= 4.0.0 < 4.3.14.3.1
pumapuma>= 4.0.0 < 4.3.14.3.1
pumapuma>= 5.0.0 < 5.3.15.3.1
pumapuma>= 5.0.0 < 5.3.15.3.1

CVSS provenance

nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
nvdv2.05.0MEDIUMAV:N/AC:L/Au:N/C:N/I:N/A:P
ghsa7.5HIGH
osv7.5HIGH
vendor_debian5.3MEDIUM
vendor_redhat5.3MEDIUM
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