UBUNTU-CVE-2021-29509

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Source
https://ubuntu.com/security/notices/UBUNTU-CVE-2021-29509
Import Source
https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-29509.json
JSON Data
https://api.osv.dev/v1/vulns/UBUNTU-CVE-2021-29509
Related
Published
2021-05-11T17:15:00Z
Modified
2021-05-11T17:15:00Z
Severity
  • 7.5 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
Summary
[none]
Details

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.

References

Affected packages

Ubuntu:20.04:LTS / puma

Package

Name
puma
Purl
pkg:deb/ubuntu/puma@3.12.4-1ubuntu2?arch=src?distro=focal

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
3.12.4-1ubuntu2

Affected versions

3.*

3.12.0-2ubuntu1
3.12.0-4ubuntu1

Ecosystem specific 

{
    "availability": "No subscription required",
    "ubuntu_priority": "medium",
    "binaries": [
        {
            "puma": "3.12.4-1ubuntu2",
            "puma-dbgsym": "3.12.4-1ubuntu2"
        }
    ]
}

Ubuntu:22.04:LTS / puma

Package

Name
puma
Purl
pkg:deb/ubuntu/puma@5.5.2-2ubuntu2?arch=src?distro=jammy

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
5.5.2-2ubuntu2

Affected versions

4.*

4.3.6-1ubuntu4

Ecosystem specific 

{
    "availability": "No subscription required",
    "ubuntu_priority": "medium",
    "binaries": [
        {
            "puma": "5.5.2-2ubuntu2",
            "puma-dbgsym": "5.5.2-2ubuntu2"
        }
    ]
}