CVE-2023-44199Network attack vector

FPC restart via prolonged routing protocol churn

Published Oct 12, 2023 · Updated Sep 18, 2024

Improper exceptional-condition handling in the Junos OS PFE on affected MX Series releases allows remote attackers to restart an FPC. With PTP configured on an FPC interface, prolonged routing protocol churn is not handled safely by the Packet Forwarding Engine and causes the card to crash and restart. Exposure requires PTP on at least one FPC interface; exploitation interrupts forwarding on the affected card without reported confidentiality or integrity impact.

CVSS severity7.5
High
EPSS probability0.54%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Improper exceptional-condition handling in the Junos OS PFE on affected MX Series releases allows remote attackers to restart an FPC. With PTP configured on an FPC interface, prolonged routing protocol churn is not handled safely by the Packet Forwarding Engine and causes the card to crash and restart. Exposure requires PTP on at least one FPC interface; exploitation interrupts forwarding on the affected card without reported confidentiality or integrity impact.

The record

CVE
CVE-2023-44199
Published
Oct 12, 2023
Updated
Sep 18, 2024
Vendor
Juniper Networks
Product
Junos OS
Classifications
CWE-754, T1499
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 12, 2023CVE publishedPublication date reported by the CVE source.
  2. Sep 18, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <20.4r3-s4
  2. Affected versionversion=0 <20.4R3-S4
  3. Affected versionversion=21.1r1 <21.1*
  4. Affected versionversion=21.1R1 <21.1*
  5. Affected versionversion=21.2 <21.2r3-s2
  6. Affected versionversion=21.2 <21.2R3-S2
  7. Affected versionversion=21.3 <21.3r3-s5
  8. Affected versionversion=21.3 <21.3R3-S5
  9. Affected versionversion=21.4 <21.4r3
  10. Affected versionversion=21.4 <21.4R3
  11. Affected versionversion=22.1 <22.1r3
  12. Affected versionversion=22.1 <22.1R3
  13. Affected versionversion=22.2 <22.2r1-s1,22.2r2
  14. Affected versionversion=22.2 <22.2R1-S1, 22.2R2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Juniper Networks · Junos OSversion=0 <20.4r3-s4; version=0 <20.4R3-S4; version=21.1r1 <21.1*; version=21.1R1 <21.1*; version=21.2 <21.2r3-s2; version=21.2 <21.2R3-S2; version=21.3 <21.3r3-s5; version=21.3 <21.3R3-S5; version=21.4 <21.4r3; version=21.4 <21.4R3; version=22.1 <22.1r3; version=22.1 <22.1R3; version=22.2 <22.2r1-s1,22.2r2; version=22.2 <22.2R1-S1, 22.2R2

Published CVSS scores

7.5Juniper NetworksCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-754Improper Check for Unusual or Exceptional Conditions
T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo