Log in Start free

Vulnerability · Published Jul 15, 2021 · Assigned by juniper

CVE-2021-0295Junos OS: QFX10K Series: Denial of Service (DoS) upon receipt of DVMRP packets received on multi-homing ESI in VXLAN.

Medium 6.1

In plain English

A medium-severity security flaw in Junos OS from Juniper Networks. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 1.1% (higher than 66% of all known vulnerabilities).

Severity (CVSS 3.1)6.1Medium
Exploit odds (30 days)1.1%top 34.2% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known

Official description

A vulnerability in the Distance Vector Multicast Routing Protocol (DVMRP) of Juniper Networks Junos OS on the QFX10K Series switches allows an attacker to trigger a packet forwarding loop, leading to a partial Denial of Service (DoS). The issue is caused by DVMRP packets looping on a multi-homed Ethernet Segment Identifier (ESI) when VXLAN is configured. DVMRP packets received on a multi-homed ESI are sent to the peer, and then incorrectly forwarded out the same ESI, violating the split horizon rule. This issue only affects QFX10K Series switches, including the QFX10002, QFX10008, and QFX10016. Other products and platforms are unaffected by this vulnerability. This issue affects Juniper Networks Junos OS on QFX10K Series: 17.3 versions prior to 17.3R3-S12; 17.4 versions prior to 17.4R3-S5; 18.1 versions prior to 18.1R3-S13; 18.2 version 18.2R1 and later versions; 18.3 versions prior to 18.3R3-S5; 18.4 versions prior to 18.4R2-S9, 18.4R3-S8; 19.1 versions prior to 19.1R3-S5; 19.2 versions prior to 19.2R1-S7, 19.2R3-S2; 19.3 versions prior to 19.3R3-S2; 19.4 versions prior to 19.4R3-S3; 20.1 versions prior to 20.1R2-S2, 20.1R3; 20.2 versions prior to 20.2R3; 20.3 versions prior to 20.3R3; 20.4 versions prior to 20.4R2.

Affected products (as reported)

VendorProductVersions
Juniper Networks Junos OS 17.3 – before 17.3R3-S1217.4 – before 17.4R3-S518.1 – before 18.1R3-S1318.2R1 – before 18.2*18.3 – before 18.3R3-S518.4 – before 18.4R2-S9, 18.4R3-S819.1 – before 19.1R3-S519.2 – before 19.2R1-S7, 19.2R3-S2

Weakness: CWE-697 · Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:L

References