CVE-2021-3571

mediumpriority · track · 29EPSS 0.019 · 80 %ileDEEURUUS
grimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
1.90% (80th) EPSS
CVSS 5.5 · medium
Is it mine?
39 products
Check your exposure
Who says so?
5 sources
cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-27

A flaw was found in the ptp4l program of the linuxptp package. When ptp4l is operating on a little-endian architecture as a PTP transparent clock, a remote attacker could send a crafted one-step sync message to cause an information leak or crash. The highest threat from this vulnerability is to data confidentiality and system availability. This flaw affects linuxptp versions before 3.1.1 and before 2.0.1.

01

remediations

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

A vendor fix is available.

  • Fixedlinuxptp-0:3.1.1-1.el8.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_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-2021:4321
  • Fixedlinuxptp-0:3.1.1-1.el8.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_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-2021:4321
  • Fixedlinuxptp-0:3.1.1-1.el8.s390x as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_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-2021:4321
  • Fixedlinuxptp-0:3.1.1-1.el8.src as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_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-2021:4321
  • Fixedlinuxptp-0:3.1.1-1.el8.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_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-2021:4321
  • Fixedlinuxptp-debuginfo-0:3.1.1-1.el8.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_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-2021:4321
  • Fixedlinuxptp-debuginfo-0:3.1.1-1.el8.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_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-2021:4321
  • Fixedlinuxptp-debuginfo-0:3.1.1-1.el8.s390x as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_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-2021:4321
  • Fixedlinuxptp-debuginfo-0:3.1.1-1.el8.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_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-2021:4321
  • Fixedlinuxptp-debugsource-0:3.1.1-1.el8.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_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-2021:4321
  • Fixedlinuxptp-debugsource-0:3.1.1-1.el8.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_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-2021:4321
  • Fixedlinuxptp-debugsource-0:3.1.1-1.el8.s390x as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_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-2021:4321
  • Fixedlinuxptp-debugsource-0:3.1.1-1.el8.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_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-2021:4321
  • Workaroundlinuxptp-0:3.1.1-1.el8.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf

    Only attackers that can connect to the `ptp4l` service can exploit this vulnerability. If `ptp4l` is bound only to a private network interface, or is protected by firewall rules to block incoming PTP management messages, the attack surface is correspondingly limited. When using the UDP IPv4 or IPv6 network transport, the following tcpdump filter can be used to detect PTP management messages: ``` (port 319 or port 320) and udp[8]&0xf=0xd ```

  • Workaroundlinuxptp-0:3.1.1-1.el8.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf

    Only attackers that can connect to the `ptp4l` service can exploit this vulnerability. If `ptp4l` is bound only to a private network interface, or is protected by firewall rules to block incoming PTP management messages, the attack surface is correspondingly limited. When using the UDP IPv4 or IPv6 network transport, the following tcpdump filter can be used to detect PTP management messages: ``` (port 319 or port 320) and udp[8]&0xf=0xd ```

  • Workaroundlinuxptp-0:3.1.1-1.el8.s390x as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf

    Only attackers that can connect to the `ptp4l` service can exploit this vulnerability. If `ptp4l` is bound only to a private network interface, or is protected by firewall rules to block incoming PTP management messages, the attack surface is correspondingly limited. When using the UDP IPv4 or IPv6 network transport, the following tcpdump filter can be used to detect PTP management messages: ``` (port 319 or port 320) and udp[8]&0xf=0xd ```

  • Workaroundlinuxptp-0:3.1.1-1.el8.src as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf

    Only attackers that can connect to the `ptp4l` service can exploit this vulnerability. If `ptp4l` is bound only to a private network interface, or is protected by firewall rules to block incoming PTP management messages, the attack surface is correspondingly limited. When using the UDP IPv4 or IPv6 network transport, the following tcpdump filter can be used to detect PTP management messages: ``` (port 319 or port 320) and udp[8]&0xf=0xd ```

  • Workaroundlinuxptp-0:3.1.1-1.el8.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf

    Only attackers that can connect to the `ptp4l` service can exploit this vulnerability. If `ptp4l` is bound only to a private network interface, or is protected by firewall rules to block incoming PTP management messages, the attack surface is correspondingly limited. When using the UDP IPv4 or IPv6 network transport, the following tcpdump filter can be used to detect PTP management messages: ``` (port 319 or port 320) and udp[8]&0xf=0xd ```

  • Workaroundlinuxptp-debuginfo-0:3.1.1-1.el8.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf

    Only attackers that can connect to the `ptp4l` service can exploit this vulnerability. If `ptp4l` is bound only to a private network interface, or is protected by firewall rules to block incoming PTP management messages, the attack surface is correspondingly limited. When using the UDP IPv4 or IPv6 network transport, the following tcpdump filter can be used to detect PTP management messages: ``` (port 319 or port 320) and udp[8]&0xf=0xd ```

  • Workaroundlinuxptp-debuginfo-0:3.1.1-1.el8.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf

    Only attackers that can connect to the `ptp4l` service can exploit this vulnerability. If `ptp4l` is bound only to a private network interface, or is protected by firewall rules to block incoming PTP management messages, the attack surface is correspondingly limited. When using the UDP IPv4 or IPv6 network transport, the following tcpdump filter can be used to detect PTP management messages: ``` (port 319 or port 320) and udp[8]&0xf=0xd ```

  • Workaroundlinuxptp-debuginfo-0:3.1.1-1.el8.s390x as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf

    Only attackers that can connect to the `ptp4l` service can exploit this vulnerability. If `ptp4l` is bound only to a private network interface, or is protected by firewall rules to block incoming PTP management messages, the attack surface is correspondingly limited. When using the UDP IPv4 or IPv6 network transport, the following tcpdump filter can be used to detect PTP management messages: ``` (port 319 or port 320) and udp[8]&0xf=0xd ```

  • Workaroundlinuxptp-debuginfo-0:3.1.1-1.el8.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf

    Only attackers that can connect to the `ptp4l` service can exploit this vulnerability. If `ptp4l` is bound only to a private network interface, or is protected by firewall rules to block incoming PTP management messages, the attack surface is correspondingly limited. When using the UDP IPv4 or IPv6 network transport, the following tcpdump filter can be used to detect PTP management messages: ``` (port 319 or port 320) and udp[8]&0xf=0xd ```

  • Workaroundlinuxptp-debugsource-0:3.1.1-1.el8.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf

    Only attackers that can connect to the `ptp4l` service can exploit this vulnerability. If `ptp4l` is bound only to a private network interface, or is protected by firewall rules to block incoming PTP management messages, the attack surface is correspondingly limited. When using the UDP IPv4 or IPv6 network transport, the following tcpdump filter can be used to detect PTP management messages: ``` (port 319 or port 320) and udp[8]&0xf=0xd ```

  • Workaroundlinuxptp-debugsource-0:3.1.1-1.el8.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf

    Only attackers that can connect to the `ptp4l` service can exploit this vulnerability. If `ptp4l` is bound only to a private network interface, or is protected by firewall rules to block incoming PTP management messages, the attack surface is correspondingly limited. When using the UDP IPv4 or IPv6 network transport, the following tcpdump filter can be used to detect PTP management messages: ``` (port 319 or port 320) and udp[8]&0xf=0xd ```

  • Workaroundlinuxptp-debugsource-0:3.1.1-1.el8.s390x as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf

    Only attackers that can connect to the `ptp4l` service can exploit this vulnerability. If `ptp4l` is bound only to a private network interface, or is protected by firewall rules to block incoming PTP management messages, the attack surface is correspondingly limited. When using the UDP IPv4 or IPv6 network transport, the following tcpdump filter can be used to detect PTP management messages: ``` (port 319 or port 320) and udp[8]&0xf=0xd ```

  • Workaroundlinuxptp-debugsource-0:3.1.1-1.el8.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf

    Only attackers that can connect to the `ptp4l` service can exploit this vulnerability. If `ptp4l` is bound only to a private network interface, or is protected by firewall rules to block incoming PTP management messages, the attack surface is correspondingly limited. When using the UDP IPv4 or IPv6 network transport, the following tcpdump filter can be used to detect PTP management messages: ``` (port 319 or port 320) and udp[8]&0xf=0xd ```

02

cvss

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

7.1
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5.5–7.1

v2.05.5mediumAV:N/AC:L/Au:S/C:P/I:N/A:Pprimary · NVD / NIST USexploitability 8 · impact 4.9
v3.17.1highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:Hprimary · NVD / NIST USexploitability 2.8 · impact 4.2
v3.17.1highAV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:Hsecondary · FSTEC (BDU) RU
v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)
v3.17.1highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:Hsecondary · Red Hat Product Security US
03

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-125USprimaryCWE-119USCWE-119USCWE-119US
04

affected products (39)

Products and version ranges known to be affected.

showing 20 of 39
05

advisories (2)

Vendor and ecosystem advisories describing this.

  • RHSA-2021:4321Red Hat Security Advisory: linuxptp security, bug fix, and enhancement update2021-11-09csaf · redhat_csafUS

    An update for linuxptp is now available for Red Hat Enterprise Linux 8. Red Hat Product Security has rated this update as having a security impact of Moderate. 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-2022-0571Red Hat Enterprise Linux: Mehrere SchwachstellenDeutsch2021-11-09csaf · cert_bundDE

    Ein entfernter, anonymer, authentisierter oder lokaler Angreifer kann mehrere Schwachstellen in Red Hat Enterprise Linux ausnutzen, um einen Cross-Site-Scripting-Angriff durchzuführen, vertrauliche Informationen offenzulegen, einen Denial-of-Service-Zustand herbeizuführen, Sicherheitsmaßnahmen zu umgehen, beliebigen Code auszuführen, Dateien zu manipulieren und einen nicht spezifizierten Angriff durchzuführen.

06

also known as (4)

Other names and identifiers for this entity.

07

sources

Which sources assert this record, and when.

cnnvdenisa_euvdfstec_bducert_bundredhat_csafNVDCVE.orgMITRE
published 2021-07-09modified 2026-06-17
09

references (15)

External citations — patches, advisories, analysis.

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