CVE-2020-1655

Vulnerability Summary

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 large packets requiring fragmentation, generating the following error messages: [LOG: Err] MQSS(0): WO: Packet Error - Error Packets 1, Connection 29 [LOG: Err] eachip_hmcif_rx_intr_handler(7259): EA[0:0]: HMCIF Rx: Injected checksum error detected on WO response - Chunk Address 0x0 [LOG: Err] MQSS(0): DRD: RORD1: CMD reorder ID error - Command 11, Reorder ID 1838, QID 0 [LOG: Err] MQSS(0): DRD: UNROLL0: HMC chunk length error in stage 5 - Chunk Address: 0x4321f3 [LOG: Err] MQSS(0): DRD: UNROLL0: HMC chunk address error in stage 5 - Chunk Address: 0x0 [LOG: Notice] Error: /fpc/8/pfe/0/cm/0/MQSS(0)/0/MQSS_CMERROR_DRD_RORD_ENG_INT_REG_CMD_FSM_STATE_ERR (0x2203cc), scope: pfe, category: functional, severity: major, module: MQSS(0), type: DRD_RORD_ENG_INT: CMD FSM State Error [LOG: Notice] Performing action cmalarm for error /fpc/8/pfe/0/cm/0/MQSS(0)/0/MQSS_CMERROR_DRD_RORD_ENG_INT_REG_CMD_FSM_STATE_ERR (0x2203cc) in module: MQSS(0) with scope: pfe category: functional level: major [LOG: Notice] Performing action get-state for error /fpc/8/pfe/0/cm/0/MQSS(0)/0/MQSS_CMERROR_DRD_RORD_ENG_INT_REG_CMD_FSM_STATE_ERR (0x2203cc) in module: MQSS(0) with scope: pfe category: functional level: major [LOG: Notice] Performing action disable-pfe for error /fpc/8/pfe/0/cm/0/MQSS(0)/0/MQSS_CMERROR_DRD_RORD_ENG_INT_REG_CMD_FSM_STATE_ERR (0x2203cc) in module: MQSS(0) 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 before 17.2R3-S4 on MX Series; 17.3 versions before 17.3R3-S8 on MX Series; 17.4 versions before 17.4R2-S10, 17.4R3-S2 on MX Series; 18.1 versions before 18.1R3-S10 on MX Series; 18.2 versions before 18.2R3-S3 on MX Series; 18.2X75 versions before 18.2X75-D41, 18.2X75-D430, 18.2X75-D65 on MX Series; 18.3 versions before 18.3R1-S7, 18.3R2-S4, 18.3R3-S1 on MX Series; 18.4 versions before 18.4R1-S7, 18.4R2-S4, 18.4R3 on MX Series; 19.1 versions before 19.1R1-S5, 19.1R2-S1, 19.1R3 on MX Series; 19.2 versions before 19.2R1-S4, 19.2R2 on MX Series; 19.3 versions before 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 before 17.2 are unaffected by this vulnerability.

Vulnerability Trend

References