CVE-2023-36850

Adjacent MPC crash via malformed CFM packet

Published Jul 14, 2023 · Updated Oct 22, 2024

Improper input-offset validation in the CFM module of Juniper Networks Junos OS allows adjacent attackers to crash MX Series MPCs. The module accepts a malformed CFM packet containing an invalid index, position, or offset, and the MPC crashes while processing it. The packet must arrive from the local broadcast domain while CFM is not configured; repeated packets sustain the service interruption.

CVSS severity6.5
Medium
EPSS probability0.30%
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 input-offset validation in the CFM module of Juniper Networks Junos OS allows adjacent attackers to crash MX Series MPCs. The module accepts a malformed CFM packet containing an invalid index, position, or offset, and the MPC crashes while processing it. The packet must arrive from the local broadcast domain while CFM is not configured; repeated packets sustain the service interruption.

The record

CVE
CVE-2023-36850
Published
Jul 14, 2023
Updated
Oct 22, 2024
Vendor
Juniper Networks
Product
Junos OS
Classifications
CWE-1285, T1498
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 14, 2023CVE publishedPublication date reported by the CVE source.
  2. Oct 22, 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=19.2 <19.2R3-S7
  2. Affected versionversion=19.3 <19.3R3-S8
  3. Affected versionversion=19.4 <19.4R3-S12
  4. Affected versionversion=20.1 <20.1*
  5. Affected versionversion=20.2 <20.2R3-S7
  6. Affected versionversion=20.3 <20.3*
  7. Affected versionversion=20.4 <20.4R3-S7
  8. Affected versionversion=21.2 <21.1R3-S5
  9. Affected versionversion=21.2 <21.2R3-S4
  10. Affected versionversion=21.3 <21.3R3-S4
  11. Affected versionversion=21.4 <21.4R3-S3
  12. Affected versionversion=22.1 <22.1R3-S2
  13. Affected versionversion=22.2 <22.2R3
  14. Affected versionversion=22.3 <22.3R2
  15. Affected versionversion=22.4 <22.4R2
  16. Affected versionversion=unspecified <19.1R3-S10

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesunauthenticated

What is affected?

Juniper Networks · Junos OSversion=19.2 <19.2R3-S7; version=19.3 <19.3R3-S8; version=19.4 <19.4R3-S12; version=20.1 <20.1*; version=20.2 <20.2R3-S7; version=20.3 <20.3*; version=20.4 <20.4R3-S7; version=21.2 <21.1R3-S5; version=21.2 <21.2R3-S4; version=21.3 <21.3R3-S4; version=21.4 <21.4R3-S3; version=22.1 <22.1R3-S2; version=22.2 <22.2R3; version=22.3 <22.3R2; version=22.4 <22.4R2; version=unspecified <19.1R3-S10

Published CVSS scores

6.5Juniper NetworksCVSS:3.1/AV:A/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)
Vectoradjacent
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-1285Improper Validation of Specified Index, Position, or Offset in Input
T1498Network 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