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NVD / CVE Program· CNA redhat

CVE-2021-3570: A flaw was found in the ptp4l program of the linuxptp package.

Noroxi assessment

Priority: Monitor (action score 36/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 2.9% (FIRST EPSS); higher than 87.2% of all records.
  • Anyone who can reach it over the internet can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: linuxptp (Debian:10) 1.9.2-1+deb10u1; linuxptp (Debian:12) 3.1-2.1; linuxptp (Debian:9) 1.8-1+deb9u1.
  • Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Upgrade to linuxptp (Debian:10) 1.9.2-1+deb10u1; linuxptp (Debian:12) 3.1-2.1; linuxptp (Debian:9) 1.8-1+deb9u1 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

A flaw was found in the ptp4l program of the linuxptp package. A missing length check when forwarding a PTP message between ports allows a remote attacker to cause an information leak, crash, or potentially remote code execution. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability. This flaw affects linuxptp versions before 3.1.1, before 2.0.1, before 1.9.3, before 1.8.1, before 1.7.1, before 1.6.1 and before 1.5.1.

HighCVSS 8.8 · v3.1—No exploit Fix available
Published
Jul 9, 2021
Updated
Jun 17, 2026
EPSS
2.9% · 87th percentile

Report tools

JSON

Action score

36

Monitor

Low priority for now.

CVSS
35 / 40 · 8.8 / 10
CISA KEV
0 / 30 · Not listed
EPSS
1 / 30 · 2.9%

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2021-3570

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
linuxptp projectlinuxptp
redhatenterprise linux
redhatenterprise linux aus
redhatenterprise linux eus
redhatenterprise linux tus
fedoraprojectfedora
debiandebian linux

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • debian debian linux10.0
  • fedoraproject fedora33
  • fedoraproject fedora34
  • linuxptp project linuxptp1.8.0 and later · before 1.8.1
  • linuxptp project linuxptp1.9.0 and later · before 1.9.3
  • linuxptp project linuxptp2.0.0 and later · before 2.0.1
  • linuxptp project linuxptp3.0.0 and later · before 3.1.1
  • linuxptp project linuxptpbefore 1.5.1
  • linuxptp project linuxptp1.6.0 and later · before 1.6.1
  • linuxptp project linuxptp1.7.0 and later · before 1.7.1
  • redhat enterprise linux6.0
  • redhat enterprise linux7.0
  • redhat enterprise linux8.0
  • redhat enterprise linux aus8.2
  • redhat enterprise linux aus8.4
  • redhat enterprise linux eus8.1
  • redhat enterprise linux eus8.2
  • redhat enterprise linux tus8.2
  • redhat enterprise linux tus8.4

Versions reported by the vendor

Affected version ranges reported by the assigning authority (redhat). Independent of NVD's CPE analysis and usually ahead of it.

  • n/a linuxptp

    • linuxptp 3.1.1, linuxptp 2.0.1, linuxptp 1.9.3, linuxptp 1.8.1, linuxptp 1.7.1, linuxptp 1.6.1, linuxptp 1.5.1affected

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Debian:10linuxptpbefore 1.9.2-1+deb10u11.9.2-1+deb10u1
Debian:12linuxptpbefore 3.1-2.13.1-2.1
Debian:9linuxptpbefore 1.8-1+deb9u11.8-1+deb9u1
openSUSE:Leap 15.2linuxptpbefore 1.8+git65.g303b08c-lp152.4.3.11.8+git65.g303b08c-lp152.4.3.1
openSUSE:Leap 15.3linuxptpbefore 3.1.1-3.3.13.1.1-3.3.1
Red Hat:enterprise_linux:7::clientlinuxptpbefore 0:2.0-2.el7_9.10:2.0-2.el7_9.1
Red Hat:enterprise_linux:7::clientlinuxptp-debuginfobefore 0:2.0-2.el7_9.10:2.0-2.el7_9.1
Red Hat:enterprise_linux:8::appstreamlinuxptpbefore 0:2.0-5.el8_4.10:2.0-5.el8_4.1
Red Hat:enterprise_linux:8::appstreamlinuxptp-debuginfobefore 0:2.0-5.el8_4.10:2.0-5.el8_4.1
Red Hat:enterprise_linux:8::appstreamlinuxptp-debugsourcebefore 0:2.0-5.el8_4.10:2.0-5.el8_4.1
Red Hat:rhel_eus:8.1::appstreamlinuxptpbefore 0:2.0-4.el8_1.10:2.0-4.el8_1.1
Red Hat:rhel_eus:8.1::appstreamlinuxptp-debuginfobefore 0:2.0-4.el8_1.10:2.0-4.el8_1.1
Red Hat:rhel_eus:8.1::appstreamlinuxptp-debugsourcebefore 0:2.0-4.el8_1.10:2.0-4.el8_1.1
Red Hat:rhel_eus:8.2::appstreamlinuxptpbefore 0:2.0-4.el8_2.10:2.0-4.el8_2.1
Red Hat:rhel_eus:8.2::appstreamlinuxptp-debuginfobefore 0:2.0-4.el8_2.10:2.0-4.el8_2.1
Red Hat:rhel_eus:8.2::appstreamlinuxptp-debugsourcebefore 0:2.0-4.el8_2.10:2.0-4.el8_2.1
Rocky Linux:8linuxptpbefore 0:2.0-5.el8_4.10:2.0-5.el8_4.1
SUSE:HPE Helion OpenStack 8linuxptpbefore 1.4-15.3.11.4-15.3.1
SUSE:Linux Enterprise Module for Server Applications 15 SP2linuxptpbefore 1.8+git65.g303b08c-3.3.11.8+git65.g303b08c-3.3.1
SUSE:Linux Enterprise Module for Server Applications 15 SP3linuxptpbefore 3.1.1-3.3.13.1.1-3.3.1

Other highest-scoring records for the same primary product.

  • CVE-2024-42861An issue in IEEE 802.1AS linuxptp v.4.2 and before allowing a remote attacker to cause a denial of service via a crafted Pdelay_Req message
    30Monitor
  • CVE-2021-3571A flaw was found in the ptp4l program of the linuxptp package.
    29Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
debian:linuxptp3.1-2.1 · Debian:12Package registry (OSV)
opensuse:linuxptp1.8+git65.g303b08c-lp152.4.3.1 · openSUSE:Leap 15.2Package registry (OSV)
red hat:linuxptp0:2.0-4.el8_2.1 · Red Hat:rhel_eus:8.2::appstreamPackage registry (OSV)
red hat:linuxptp-debuginfo0:2.0-4.el8_2.1 · Red Hat:rhel_eus:8.2::appstreamPackage registry (OSV)
red hat:linuxptp-debugsource0:2.0-4.el8_2.1 · Red Hat:rhel_eus:8.2::appstreamPackage registry (OSV)
rocky linux:linuxptp0:2.0-5.el8_4.1 · Rocky Linux:8Package registry (OSV)
suse:linuxptp1.4-15.3.1 · SUSE:HPE Helion OpenStack 8Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

All national notices →

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • A low-privileged account is enough.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
high · data can be read
Integrity
high · data or configuration can be modified
Availability
high · the service can be disrupted
Attack vector
Network
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality impact
High
Integrity impact
High
Availability impact
High

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

nvd-primary

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

All records