CVE-2022-21716

mediumpriority · track · 31EPSS 0.035 · 89 %ileDEEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

3.51% (89th) EPSS

CVSS 5 · medium

Is it mine?

36 products

Check your exposure

Who says so?

7 sources

cnnvd · enisa_euvd · fstec_bdu · osv

EPSS · scored 2026-10-27

Twisted is an event-based framework for internet applications, supporting Python 3.6+. Prior to 22.2.0, Twisted SSH client and server implement is able to accept an infinite amount of data for the peer's SSH version identifier. This ends up with a buffer using all the available memory. The attach is a simple as `nc -rv localhost 22 < /dev/zero`. A patch is available in version 22.2.0. There are currently no known workarounds.

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

Fixedpython-twisted-0:16.4.1-19.el8ost.src as a component of Red Hat OpenStack Platform 16.1redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2022:0982
Fixedpython-twisted-debugsource-0:16.4.1-19.el8ost.ppc64le as a component of Red Hat OpenStack Platform 16.1redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2022:0982
Fixedpython-twisted-debugsource-0:16.4.1-19.el8ost.x86_64 as a component of Red Hat OpenStack Platform 16.1redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2022:0982
Fixedpython3-twisted-0:16.4.1-19.el8ost.ppc64le as a component of Red Hat OpenStack Platform 16.1redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2022:0982
Fixedpython3-twisted-0:16.4.1-19.el8ost.x86_64 as a component of Red Hat OpenStack Platform 16.1redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2022:0982
Fixedpython3-twisted-debuginfo-0:16.4.1-19.el8ost.ppc64le as a component of Red Hat OpenStack Platform 16.1redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2022:0982
Fixedpython3-twisted-debuginfo-0:16.4.1-19.el8ost.x86_64 as a component of Red Hat OpenStack Platform 16.1redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2022:0982
Fixedpython-twisted-0:16.4.1-19.el8ost.src as a component of Red Hat OpenStack Platform 16.2redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2022:0992
Fixedpython-twisted-debugsource-0:16.4.1-19.el8ost.ppc64le as a component of Red Hat OpenStack Platform 16.2redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2022:0992
Fixedpython-twisted-debugsource-0:16.4.1-19.el8ost.x86_64 as a component of Red Hat OpenStack Platform 16.2redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2022:0992
Fixedpython3-twisted-0:16.4.1-19.el8ost.ppc64le as a component of Red Hat OpenStack Platform 16.2redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2022:0992
Fixedpython3-twisted-0:16.4.1-19.el8ost.x86_64 as a component of Red Hat OpenStack Platform 16.2redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2022:0992
Fixedpython3-twisted-debuginfo-0:16.4.1-19.el8ost.ppc64le as a component of Red Hat OpenStack Platform 16.2redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2022:0992
Fixedpython3-twisted-debuginfo-0:16.4.1-19.el8ost.x86_64 as a component of Red Hat OpenStack Platform 16.2redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2022:0992

cvss

Technical severity, 0–10. One row per scoring source.

7.5

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5–7.5

v2.05mediumAV:N/AC:L/Au:N/C:N/I:N/A:Pprimary · NVD / NIST USexploitability 10 · impact 2.9

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 3.6

v3.17.5highAV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · FSTEC (BDU) RU

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · ENISA EU

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · security-advisories@github.comexploitability 3.9 · impact 3.6

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · OSV

v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · Red Hat Product Security US

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: poc · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-770USprimaryCWE-120USCWE-120USCWE-120USCWE-770USCWE-770US

affected products (36)

Products and version ranges known to be affected.

Oracle Linuxall versionscert_bundDEcpe:/o:oracle:linux:-
Xerox FreeFlow Print Server 7all versionscert_bundDEcpe:/a:xerox:freeflow_print_server:7
Xerox FreeFlow Print Server 9all versionscert_bundDEcpe:/a:xerox:freeflow_print_server:9
twisted twisted≤ < 22.2.0enisa_euvdEU
Glyph Lefkowitz Twisted21.7.0 → 22.2.0fstec_bduRU
АО «Концерн ВНИИНС» ОС ОН «Стрелец»≤ 16.01.2023fstec_bduRU
АО «НППКТ» ОСОН ОСнова Оnyx≤ 2.5.2fstec_bduRU
ООО «Ред Софт» РЕД ОС≤ 7.3fstec_bduRU
ООО «РусБИТех-Астра» Astra Linux Special Edition≤ 1.7fstec_bduRU
ООО «РусБИТех-Астра» Astra Linux Special Edition≤ 4.7fstec_bduRU
ООО «РусБИТех-Астра» Astra Linux Special Edition≤ 1.6 «Смоленск»fstec_bduRU
ООО «РусБИТех-Астра» Astra Linux Special Edition для «Эльбрус»≤ 8.1 «Ленинград»fstec_bduRU
Сообщество свободного программного обеспечения Debian GNU/Linux≤ 10fstec_bduRU
Сообщество свободного программного обеспечения Debian GNU/Linux≤ 11fstec_bduRU
debian debian linux= 9.0nvdUScpe:2.3:o:debian:debian_linux:*:*:*:*:*:*:*:*
fedoraproject fedora= 35nvdUScpe:2.3:o:fedoraproject:fedora:*:*:*:*:*:*:*:*
fedoraproject fedora= 36nvdUScpe:2.3:o:fedoraproject:fedora:*:*:*:*:*:*:*:*
oracle http server= 12.2.1.3.0nvdUScpe:2.3:a:oracle:http_server:*:*:*:*:*:*:*:*
oracle http server= 12.2.1.4.0nvdUScpe:2.3:a:oracle:http_server:*:*:*:*:*:*:*:*
oracle zfs storage appliance kit= 8.8nvdUScpe:2.3:a:oracle:zfs_storage_appliance_kit:*:*:*:*:*:*:*:*

showing 20 of 36

advisories (8)

Vendor and ecosystem advisories describing this.

RHSA-2022:0982Red Hat Security Advisory: Red Hat OpenStack Platform 16.1 (python-twisted) security update2022-03-24csaf · redhat_csafUS
An update for python-twisted is now available for Red Hat OpenStack Platform 16.1 (Train). Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.
RHSA-2022:0992Red Hat Security Advisory: Red Hat OpenStack Platform 16.2 (python-twisted) security update2022-03-23csaf · redhat_csafUS
An update for python-twisted is now available for Red Hat OpenStack Platform 16.2 (Train). Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.
WID-SEC-W-2022-0250Red Hat OpenStack: Mehrere SchwachstellenDeutsch2022-03-23csaf · cert_bundDE
Ein entfernter, anonymer oder authentisierter Angreifer kann mehrere Schwachstellen in Red Hat OpenStack ausnutzen, um vertrauliche Informationen offenzulegen, Sicherheitsmaßnahmen zu umgehen und einen Denial-of-Service-Zustand zu verursachen.
WID-SEC-W-2022-0302Xerox FreeFlow Print Server: Mehrere Schwachstellen ermöglichen Ausführen von beliebigem Programmcode mit AdministratorrechtenDeutsch2022-06-14csaf · cert_bundDE
Ein entfernter, authentisierter Angreifer kann mehrere Schwachstellen in Xerox FreeFlow Print Server ausnutzen, um beliebigen Programmcode auszuführen, einen Cross-Site-Scripting-Angriff durchzuführen, Informationen offenzulegen, einen Denial-of-Service-Zustand zu verursachen oder Dateien zu manipulieren.
WID-SEC-W-2022-0432Xerox FreeFlow Print Server: Mehrere SchwachstellenDeutsch2022-06-21csaf · cert_bundDE
Ein entfernter, authentisierter Angreifer kann mehrere Schwachstellen in Xerox FreeFlow Print Server ausnutzen, um die Vertraulichkeit, Verfügbarkeit und Integrität zu gefährden.
WID-SEC-W-2022-1335Xerox FreeFlow Print Server: Mehrere SchwachstellenDeutsch2022-09-07csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Xerox FreeFlow Print Server ausnutzen, um die Vertraulichkeit, Verfügbarkeit und Integrität des Systems zu gefährden.
GHSA-rv6r-3f5q-9rgxTwisted SSH client and server deny of service during SSH handshake.2022-03-03ghsa · osvUS
### Impact The Twisted SSH client and server implementation naively accepted an infinite amount of data for the peer's SSH version identifier. A malicious peer can trivially craft a request that uses all available memory and crash the server, resulting in denial of service. The attack is as simple as `nc -rv localhost 22 < /dev/zero`. ### Patches The issue was fix in GitHub commit https://github.com/twisted/twisted/commit/98387b39e9f0b21462f6abc7a1325dc370fcdeb1 A fix is available in Twisted 22.2.0. ### Workarounds * Limit access to the SSH server only to trusted source IP addresses. * Connect over SSH only to trusted destination IP addresses. ### References Reported at https://twistedmatrix.com/trac/ticket/10284 Discussions at https://github.com/twisted/twisted/security/advisories/GHSA-rv6r-3f5q-9rgx ### For more information Found by vin01
PYSEC-2022-1602022-03-03vendor · osvUS
Twisted is an event-based framework for internet applications, supporting Python 3.6+. Prior to 22.2.0, Twisted SSH client and server implement is able to accept an infinite amount of data for the peer's SSH version identifier. This ends up with a buffer using all the available memory. The attach is a simple as `nc -rv localhost 22 < /dev/zero`. A patch is available in version 22.2.0. There are currently no known workarounds.

also known as (7)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu osv cert_bund nvd redhat_csaf NVD CVE.org MITRE

published 2022-03-03modified 2026-06-17

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references (46)

External citations — patches, advisories, analysis.

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