CVE-2020-1649

Junos OS: MX Series: PFE crash on MPC7/8/9 upon receipt of small fragments requiring reassembly

HIGH

7.5

CVSS Score

Published: July 17, 2020 at 06:40 PM UTC

Updated: June 17, 2026 at 03:02 AM UTC

16 products affected across 2 vendorsJunosMx480Mx960

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Severity

HIGH7.5

Exploit prediction

EPSS 1%

Description

When a device running Juniper Networks Junos OS with MPC7, MPC8, or MPC9 line cards installed and the system is configured for inline IP reassembly, used by L2TP, MAP-E, GRE, and IPIP, the packet forwarding engine (PFE) will become disabled upon receipt of small fragments requiring reassembly, generating the following error messages: [LOG: Err] MQSS(2): WO: Packet Error - Error Packets 1, Connection 29 [LOG: Err] eachip_hmcif_rx_intr_handler(7259): EA[2:0]: HMCIF Rx: Injected checksum error detected on WO response - Chunk Address 0x0 [LOG: Err] MQSS(2): DRD: RORD1: CMD reorder ID error - Command 11, Reorder ID 1960, QID 0 [LOG: Err] MQSS(2): DRD: UNROLL0: HMC chunk address error in stage 5 - Chunk Address: 0xc38fb1 [LOG: Notice] Error: /fpc/0/pfe/0/cm/0/MQSS(2)/2/MQSS_CMERROR_DRD_RORD_ENG_INT_REG_CMD_FSM_STATE_ERR (0x2203cc), scope: pfe, category: functional, severity: major, module: MQSS(2), type: DRD_RORD_ENG_INT: CMD FSM State Error [LOG: Notice] Performing action cmalarm for error /fpc/0/pfe/0/cm/0/MQSS(2)/2/MQSS_CMERROR_DRD_RORD_ENG_INT_REG_CMD_FSM_STATE_ERR (0x2203cc) in module: MQSS(2) with scope: pfe category: functional level: major [LOG: Notice] Performing action get-state for error /fpc/0/pfe/0/cm/0/MQSS(2)/2/MQSS_CMERROR_DRD_RORD_ENG_INT_REG_CMD_FSM_STATE_ERR (0x2203cc) in module: MQSS(2) with scope: pfe category: functional level: major [LOG: Notice] Performing action disable-pfe for error /fpc/0/pfe/0/cm/0/MQSS(2)/2/MQSS_CMERROR_DRD_RORD_ENG_INT_REG_CMD_FSM_STATE_ERR (0x2203cc) in module: MQSS(2) with scope: pfe category: functional level: major By continuously sending fragmented packets that cannot be reassembled, an attacker can repeatedly disable the PFE causing a sustained Denial of Service (DoS). This issue affects Juniper Networks Junos OS: 17.2 versions prior to 17.2R3-S4 on MX Series; 17.3 versions prior to 17.3R3-S8 on MX Series; 17.4 versions prior to 17.4R2-S9, 17.4R3-S1 on MX Series; 18.1 versions prior to 18.1R3-S10 on MX Series; 18.2 versions prior to 18.2R2-S6, 18.2R3-S3 on MX Series; 18.2X75 versions prior to 18.2X75-D34, 18.2X75-D41, 18.2X75-D53, 18.2X75-D65, 18.2X75-D430 on MX Series; 18.3 versions prior to 18.3R1-S7, 18.3R2-S4, 18.3R3-S2 on MX Series; 18.4 versions prior to 18.4R1-S6, 18.4R2-S4, 18.4R3 on MX Series; 19.1 versions prior to 19.1R1-S4, 19.1R2-S1, 19.1R3 on MX Series; 19.2 versions prior to 19.2R1-S3, 19.2R2 on MX Series; 19.3 versions prior to 19.3R2-S2, 19.3R3 on MX Series. This issue is specific to inline IP reassembly, introduced in Junos OS 17.2. Versions of Junos OS prior to 17.2 are unaffected by this vulnerability.

Affected

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

Junos · Juniper Networks

95%

17.2 ≤ v < 17.2R3-S417.3 ≤ v < 17.3R3-S817.4 ≤ v < 17.4R2-S9, 17.4R3-S118.1 ≤ v < 18.1R3-S1018.2 ≤ v < 18.2R2-S6, 18.2R3-S318.2X75 ≤ v < 18.2X75-D34, 18.2X75-D41, 18.2X75-D53, 18.2X75-D65, 18.2X75-D43018.3 ≤ v < 18.3R1-S7, 18.3R2-S4, 18.3R3-S218.4 ≤ v < 18.4R1-S6, 18.4R2-S4, 18.4R319.1 ≤ v < 19.1R1-S4, 19.1R2-S1, 19.1R319.2 ≤ v < 19.2R1-S3, 19.2R219.3 ≤ v < 19.3R2-S2, 19.3R317.2 17.2 r1 17.2 r1-s1 17.2 r1-s2 17.2 r1-s3 17.2 r1-s4 17.2 r1-s5 17.2 r1-s7 17.2 r1-s8 17.2 r2 17.2 r2-s11 17.2 r2-s6 17.2 r2-s7 17.2 r3-s1 17.2 r3-s2 17.2 r3-s3 17.3 17.3 r1-s1 17.3 r2 17.3 r2-s1 17.3 r2-s2 17.3 r2-s3 17.3 r2-s4 17.3 r3 17.3 r3-s1 17.3 r3-s2 17.3 r3-s3 17.3 r3-s4 17.3 r3-s7 17.4 17.4 r1 17.4 r1-s1 17.4 r1-s2 17.4 r1-s4 17.4 r1-s5 17.4 r1-s6 17.4 r1-s7 17.4 r2 17.4 r2-s1 17.4 r2-s10 17.4 r2-s2 17.4 r2-s3 17.4 r2-s4 17.4 r2-s5 17.4 r2-s6 17.4 r2-s7 17.4 r2-s8 17.4 r3 18.1 18.1 r1 18.1 r2 18.1 r2-s1 18.1 r2-s2 18.1 r2-s4 18.1 r3 18.1 r3-s1 18.1 r3-s2 18.1 r3-s3 18.1 r3-s4 18.1 r3-s6 18.1 r3-s7 18.1 r3-s8 18.1 r3-s9 18.2 18.2 r1 18.2 r1-s3 18.2 r1-s4 18.2 r1-s5 18.2 r2 18.2 r2-s1 18.2 r2-s2 18.2 r2-s3 18.2 r2-s4 18.2 r2-s5 18.2 r3 18.2 r3-s1 18.2 r3-s2 18.2X7518.2x7518.2x75 d20 18.2x75 d30 18.3 18.3 r1 18.3 r1-s1 18.3 r1-s2 18.3 r1-s3 18.3 r1-s5 18.3 r1-s6 18.3 r2 18.3 r2-s1 18.3 r2-s2 18.3 r2-s3 18.3 r3 18.3 r3-s1 18.4 18.4 r1 18.4 r1-s1 18.4 r1-s2 18.4 r1-s5 18.4 r2 18.4 r2-s1 18.4 r2-s2 18.4 r2-s3 19.1 19.1 r1 19.1 r1-s1 19.1 r1-s2 19.1 r1-s3 19.1 r2 19.2 19.2 r1 19.2 r1-s1 19.2 r1-s2 19.3 19.3 r1 19.3 r1-s1 19.3 r2 19.3 r2-s1

Vendor states this is fixed in 17.2 (unaffected)

Affected range stops below 17.2R3-S4, so it looks safe — our inference, not a vendor statement

Affected range stops below 17.3R3-S8, so it looks safe — our inference, not a vendor statement

Affected range stops below 17.4R2-S9, 17.4R3-S1, so it looks safe — our inference, not a vendor statement

Affected range stops below 18.1R3-S10, so it looks safe — our inference, not a vendor statement

Affected range stops below 18.2R2-S6, 18.2R3-S3, so it looks safe — our inference, not a vendor statement

Affected range stops below 18.2X75-D34, 18.2X75-D41, 18.2X75-D53, 18.2X75-D65, 18.2X75-D430, so it looks safe — our inference, not a vendor statement

Affected range stops below 18.3R1-S7, 18.3R2-S4, 18.3R3-S2, so it looks safe — our inference, not a vendor statement

Affected range stops below 18.4R1-S6, 18.4R2-S4, 18.4R3, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.1R1-S4, 19.1R2-S1, 19.1R3, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.2R1-S3, 19.2R2, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.3R2-S2, 19.3R3, so it looks safe — our inference, not a vendor statement

juniper-mx10 (environment) · juniper-mx10000 (environment) · juniper-mx10003 (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

Mx104 · Juniperdevice

80%

All versions