Skip to main content

Junos CVE-2020-1665

MEDIUM
Incomplete Filtering of Multiple Instances of Special Elements (CWE-794)
2020-10-16 sirt@juniper.net
5.3
CVSS 3.1 · Vendor: juniper
View

Vulnerability Assessment

Weakness
CWE
ASVS 5.0
V2 - Validation and Business Logic Incomplete filtering of multiple instances
Impact

CVSS score of 5.3 (MEDIUM). Attack characteristics: network attack vector, low complexity, no privileges required, no user interaction not required.

Exploit ScenarioDerived

This vulnerability can be exploited remotely over the network. Successful exploitation could compromise the medium-severity affected system.

This Month Plan within 30 days. Why: MEDIUM severity (CVSS 4.0-6.9).
No patch listed yet 1.3% exploitation probability (EPSS)

Get an e-mail when this CVE is exploited, patched or re-scored. Free account.

Alert me

AnalysisAI

On Juniper Networks MX Series and EX9200 Series, in a certain condition the IPv6 Distributed Denial of Service (DDoS) protection might not take affect when it reaches the threshold condition. Rated medium severity (CVSS 5.3), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.

RemediationAI

No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.

Affects your stack

Find out whether the stacks and servers you run are on an affected version.

Checking this CVE against your own stacks and servers is part of the Basic plan and up.

Technical ContextAI · show details

This vulnerability is classified under CWE-794. On Juniper Networks MX Series and EX9200 Series, in a certain condition the IPv6 Distributed Denial of Service (DDoS) protection might not take affect when it reaches the threshold condition. The DDoS protection allows the device to continue to function while it is under DDoS attack, protecting both the Routing Engine (RE) and the Flexible PIC Concentrator (FPC) during the DDoS attack. When this issue occurs, the RE and/or the FPC can become overwhelmed, which could disrupt network protocol operations and/or interrupt traffic. This issue does not affect IPv4 DDoS protection. Please refer to https://kb.juniper.net/KB25385 for the list of Trio-based PFEs.2 versions prior to 17.2R3-S4; 17.2X75 versions prior to 17.2X75-D102, 17.2X75-D110; 17.3 versions prior to 17.3R3-S8; 17.4 versions prior to 17.4R2-S11, 17.4R3-S2; 18.2 versions prior to 18.2R2-S7, 18.2R3, 18.2R3-S3; 18.2X75 versions prior to 18.2X75-D30; 18.3 versions prior to 18.3R2-S4, 18.3R3-S2. Affected products include: Juniper Junos. Version information: prior to 17.2.

Severity by source

Vendor (juniper) PRIMARY 5.3 MEDIUM
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Primary rating from Vendor (juniper) · only source for this CVE.

CVSS VectorVendor: juniper

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
Low

DescriptionCVE.org

On Juniper Networks MX Series and EX9200 Series, in a certain condition the IPv6 Distributed Denial of Service (DDoS) protection might not take affect when it reaches the threshold condition. The DDoS protection allows the device to continue to function while it is under DDoS attack, protecting both the Routing Engine (RE) and the Flexible PIC Concentrator (FPC) during the DDoS attack. When this issue occurs, the RE and/or the FPC can become overwhelmed, which could disrupt network protocol operations and/or interrupt traffic. This issue does not affect IPv4 DDoS protection. This issue affects MX Series and EX9200 Series with Trio-based PFEs (Packet Forwarding Engines). Please refer to https://kb.juniper.net/KB25385 for the list of Trio-based PFEs. This issue affects Juniper Networks Junos OS on MX series and EX9200 Series: 17.2 versions prior to 17.2R3-S4; 17.2X75 versions prior to 17.2X75-D102, 17.2X75-D110; 17.3 versions prior to 17.3R3-S8; 17.4 versions prior to 17.4R2-S11, 17.4R3-S2; 18.2 versions prior to 18.2R2-S7, 18.2R3, 18.2R3-S3; 18.2X75 versions prior to 18.2X75-D30; 18.3 versions prior to 18.3R2-S4, 18.3R3-S2.

Threat Intelligence Overview

EPSS Score
1.3%
Top 33% exploitable
Data Quality
2 sources
Confidence: Low

How this decision was reached

The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.

SignalValue
Severity MEDIUM
CISA KEV No
Public POC No
EPSS 1.3%
Patch available No
Active threat No
Deciding rule
MEDIUM severity (CVSS 4.0-6.9)
What every action level means
Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.
Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.
This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.
This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.
Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

SSVC AssessmentENISA

SSVC Decision· derived
Scheduled
Exploitation· derived
None
System Exposure· derived
Open
Automatable· derived
Yes
Human Impact· derived
Medium

Priority Score

27
Low Medium High Critical
KEV: 0
EPSS: +1
CVSS: +26
PoC: 0
Weaponized: 0
Threat intel: 0
Gov advisory: 0

Attack Technique

Denial of Service attacks render applications or systems unavailable by overwhelming resources or triggering failure conditions.

Affected Products (CPE)CVE.org

cpe:2.3:o:juniper:junos:17.2:-:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:17.2:r1:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:17.2:r1-s1:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:17.2:r1-s2:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:17.2:r1-s3:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:17.2:r1-s4:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:17.2:r1-s5:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:17.2:r1-s7:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:17.2:r1-s8:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:17.2:r2:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:17.2:r2-s11:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:17.2:r2-s6:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:17.2:r2-s7:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:17.2:r3-s1:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:17.2:r3-s2:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:17.2:r3-s3:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:17.2x75:-:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:17.2x75:d50:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:17.2x75:d70:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:17.2x75:d92:*:*:*:*:*:*
+ 67 more

More in Junos

View all
CVE-2016-1285 MEDIUM
6.8 Mar 09

named in ISC BIND 9.x before 9.9.8-P4 and 9.10.x before 9.10.3-P4 does not properly handle DNAME records when parsing fe

CVE-2016-1286 HIGH
8.6 Mar 09

named in ISC BIND 9.x before 9.9.8-P4 and 9.10.x before 9.10.3-P4 allows remote attackers to cause a denial of service (

CVE-2025-21590 MEDIUM
6.7 Mar 12

A security vulnerability in An Improper (CVSS 6.7) that allows a local attacker with high privileges. Risk factors: acti

CVE-2023-36845 CRITICAL POC
9.8 Aug 17

A PHP External Variable Modification vulnerability in J-Web of Juniper Networks Junos OS on EX Series and SRX Series all

CVE-2013-6618 CRITICAL POC
9.0 Nov 05

jsdm/ajax/port.php in J-Web in Juniper Junos before 10.4R13, 11.4 before 11.4R7, 12.1 before 12.1R5, 12.2 before 12.2R3,

CVE-2014-6380 HIGH POC
7.8 Oct 14

Juniper Junos 11.4 before R11, 12.1 before R9, 12.1X44 before D30, 12.1X45 before D20, 12.1X46 before D15, 12.1X47 befor

CVE-2021-0253 HIGH POC
7.8 Apr 22

NFX Series devices using Juniper Networks Junos OS are susceptible to a local command execution vulnerability thereby al

CVE-2021-0252 HIGH POC
7.8 Apr 22

NFX Series devices using Juniper Networks Junos OS are susceptible to a local code execution vulnerability thereby allow

CVE-2019-0053 HIGH POC
7.8 Jul 11

Insufficient validation of environment variables in the telnet client supplied in Junos OS can lead to stack-based buffe

CVE-2023-22415 HIGH POC
7.5 Jan 13

An Out-of-Bounds Write vulnerability in the H.323 ALG of Juniper Networks Junos OS allows an unauthenticated, network-ba

CVE-2022-22223 HIGH POC
7.5 Oct 18

On QFX10000 Series devices using Juniper Networks Junos OS when configured as transit IP/MPLS penultimate hop popping (P

CVE-2022-22209 HIGH POC
7.5 Jul 20

A Missing Release of Memory after Effective Lifetime vulnerability in the kernel of Juniper Networks Junos OS allows an

This site uses cookies essential for authentication and security. No tracking or analytics cookies are used. Privacy Policy