CVE-2023-36850

Junos OS: MX Series: An MPC will crash upon receipt of a malformed CFM packet.

MEDIUM

6.5

CVSS Score

Published: July 14, 2023 at 06:06 PM UTC

Updated: June 17, 2026 at 06:07 AM UTC

18 products affected across 2 vendorsJunosMx960Mx480

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Severity

MEDIUM6.5

Exploit prediction

EPSS 0.3%

SSVC

No known exploit

Description

An Improper Validation of Specified Index, Position, or Offset in Input vulnerability in the Connectivity Fault Management(CFM) module of Juniper Networks Junos OS on MX Series(except MPC10, MPC11 and LC9600) allows an adjacent attacker on the local broadcast domain to cause a Denial of Service(DoS). Upon receiving a malformed CFM packet, the MPC crashes. Continued receipt of these packets causes a sustained denial of service. This issue can only be triggered when CFM hasn't been configured. This issue affects: Juniper Networks Junos OS All versions prior to 19.1R3-S10 on MX Series; 19.2 versions prior to 19.2R3-S7 on MX Series; 19.3 versions prior to 19.3R3-S8 on MX Series; 19.4 versions prior to 19.4R3-S12 on MX Series; 20.1 version 20.1R1 and later versions on MX Series; 20.2 versions prior to 20.2R3-S7 on MX Series; 20.3 version 20.3R1 and later versions on MX Series; 20.4 versions prior to 20.4R3-S7 on MX Series; 21.1 versions prior to 21.1R3-S5 on MX Series; 21.2 versions prior to 21.2R3-S4 on MX Series; 21.3 versions prior to 21.3R3-S4 on MX Series; 21.4 versions prior to 21.4R3-S3 on MX Series; 22.1 versions prior to 22.1R3-S2 on MX Series; 22.2 versions prior to 22.2R3 on MX Series; 22.3 versions prior to 22.3R2, 22.3R3 on MX Series; 22.4 versions prior to 22.4R2 on MX Series.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Junos · Juniper Networks

95%

v < 19.1R3-S1019.2 ≤ v < 19.2R3-S719.3 ≤ v < 19.3R3-S819.4 ≤ v < 19.4R3-S1220.1 ≤ v < 20.1*20.2 ≤ v < 20.2R3-S720.3 ≤ v < 20.3*20.4 ≤ v < 20.4R3-S721.2 ≤ v < 21.1R3-S521.2 ≤ v < 21.2R3-S421.3 ≤ v < 21.3R3-S421.4 ≤ v < 21.4R3-S322.1 ≤ v < 22.1R3-S222.2 ≤ v < 22.2R322.3 ≤ v < 22.3R222.4 ≤ v < 22.4R219.1 19.1 r1 19.1 r1-s1 19.1 r1-s2 19.1 r1-s3 19.1 r1-s4 19.1 r1-s5 19.1 r1-s6 19.1 r2 19.1 r2-s1 19.1 r2-s2 19.1 r2-s3 19.1 r3 19.1 r3-s1 19.1 r3-s2 19.1 r3-s3 19.1 r3-s4 19.1 r3-s5 19.1 r3-s6 19.1 r3-s7 19.1 r3-s8 19.1 r3-s9 19.2 19.2 r1 19.2 r1-s1 19.2 r1-s2 19.2 r1-s3 19.2 r1-s4 19.2 r1-s5 19.2 r1-s6 19.2 r1-s7 19.2 r1-s8 19.2 r1-s9 19.2 r2 19.2 r2-s1 19.2 r3 19.2 r3-s1 19.2 r3-s2 19.2 r3-s3 19.2 r3-s4 19.2 r3-s5 19.2 r3-s6 19.3 19.3 r1 19.3 r1-s1 19.3 r2 19.3 r2-s1 19.3 r2-s2 19.3 r2-s3 19.3 r2-s4 19.3 r2-s5 19.3 r2-s6 19.3 r2-s7 19.3 r3 19.3 r3-s1 19.3 r3-s2 19.3 r3-s3 19.3 r3-s4 19.3 r3-s5 19.3 r3-s6 19.3 r3-s7 19.4 19.4 r1 19.4 r1-s1 19.4 r1-s2 19.4 r1-s3 19.4 r1-s4 19.4 r2 19.4 r2-s1 19.4 r2-s2 19.4 r2-s3 19.4 r2-s4 19.4 r2-s5 19.4 r2-s6 19.4 r2-s7 19.4 r3 19.4 r3-s1 19.4 r3-s10 19.4 r3-s11 19.4 r3-s2 19.4 r3-s3 19.4 r3-s4 19.4 r3-s5 19.4 r3-s6 19.4 r3-s7 19.4 r3-s8 19.4 r3-s9 20.1 20.1 r1 20.1 r1-s1 20.1 r1-s2 20.1 r1-s3 20.1 r1-s4 20.1 r2 20.1 r2-s1 20.1 r2-s2 20.1 r3 20.1 r3-s1 20.1 r3-s2 20.1 r3-s3 20.1 r3-s4 20.1 r3-s5 20.2 20.2 r1 20.2 r1-s1 20.2 r1-s2 20.2 r1-s3 20.2 r2 20.2 r2-s1 20.2 r2-s2 20.2 r2-s3 20.2 r3 20.2 r3-s1 20.2 r3-s2 20.2 r3-s3 20.2 r3-s4 20.2 r3-s5 20.2 r3-s6 20.3 20.3 r1 20.3 r1-s1 20.3 r1-s2 20.3 r2 20.3 r2-s1 20.3 r3 20.3 r3-s1 20.3 r3-s2 20.3 r3-s3 20.3 r3-s4 20.3 r3-s5 20.3 r3-s6 20.4 20.4 r1 20.4 r1-s1 20.4 r2 20.4 r2-s1 20.4 r2-s2 20.4 r3 20.4 r3-s1 20.4 r3-s2 20.4 r3-s3 20.4 r3-s4 20.4 r3-s5 20.4 r3-s6 21.1 21.1 r1 21.1 r1-s1 21.1 r2 21.1 r2-s1 21.1 r2-s2 21.1 r3 21.1 r3-s1 21.1 r3-s2 21.1 r3-s3 21.1 r3-s4 21.2 21.2 r1 21.2 r1-s1 21.2 r1-s2 21.2 r2 21.2 r2-s1 21.2 r2-s2 21.2 r3 21.2 r3-s1 21.2 r3-s2 21.2 r3-s3 21.3 21.3 r1 21.3 r1-s1 21.3 r1-s2 21.3 r2 21.3 r2-s1 21.3 r2-s2 21.3 r3 21.3 r3-s1 21.3 r3-s2 21.3 r3-s3 21.4 21.4 r1 21.4 r1-s1 21.4 r1-s2 21.4 r2 21.4 r2-s1 21.4 r2-s2 21.4 r3 21.4 r3-s1 21.4 r3-s2 22.1 22.1 r1 22.1 r1-s1 22.1 r1-s2 22.1 r2 22.1 r2-s1 22.1 r2-s2 22.1 r3 22.1 r3-s1 22.2 22.2 r1 22.2 r1-s1 22.2 r1-s2 22.2 r2 22.2 r2-s1 22.2 r2-s2 22.3 22.3 r1 22.3 r1-s1 22.3 r1-s2 22.4 22.4 r1 22.4 r1-s1 22.4 r1-s2

Affected range stops below 19.1R3-S10, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.2R3-S7, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.3R3-S8, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.4R3-S12, so it looks safe — our inference, not a vendor statement

Affected range stops below 20.1*, so it looks safe — our inference, not a vendor statement

Affected range stops below 20.2R3-S7, so it looks safe — our inference, not a vendor statement

Affected range stops below 20.3*, so it looks safe — our inference, not a vendor statement

Affected range stops below 20.4R3-S7, so it looks safe — our inference, not a vendor statement

Affected range stops below 21.1R3-S5, so it looks safe — our inference, not a vendor statement

Affected range stops below 21.2R3-S4, so it looks safe — our inference, not a vendor statement

Affected range stops below 21.3R3-S4, so it looks safe — our inference, not a vendor statement

Affected range stops below 21.4R3-S3, so it looks safe — our inference, not a vendor statement

Affected range stops below 22.1R3-S2, so it looks safe — our inference, not a vendor statement

Affected range stops below 22.2R3, so it looks safe — our inference, not a vendor statement

Affected range stops below 22.3R2, so it looks safe — our inference, not a vendor statement

Affected range stops below 22.4R2, so it looks safe — our inference, not a vendor statement

juniper-mx10 (environment) · juniper-mx10000 (environment) · juniper-mx10003 (environment) · juniper-mx10008 (environment) · juniper-mx10016 (environment) · juniper-mx104 (environment) · juniper-mx150 (environment) · juniper-mx2008 (environment) · juniper-mx2010 (environment) · juniper-mx2020 (environment) · juniper-mx204 (environment) · juniper-mx240 (environment) · juniper-mx40 (environment) · juniper-mx480 (environment) · juniper-mx5 (environment) · juniper-mx80 (environment) · juniper-mx960 (environment)

Mx10 · Juniperdevice

80%

All versions

Mx10000 · Juniperdevice

80%

All versions

Mx10003 · Juniperdevice

80%

All versions

Mx10008 · Juniperdevice

80%

All versions