CVE-2021-0210

Junos OS: Privilege escalation in J-Web due to arbitrary command and code execution via information disclosure from another users active session

MEDIUM

6.8

CVSS Score

Published: January 15, 2021 at 05:35 PM UTC

Updated: June 17, 2026 at 03:29 AM UTC

1 product affected across 1 vendorJunos

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Severity

MEDIUM6.8

Exploit prediction

EPSS 1%

Description

An Information Exposure vulnerability in J-Web of Juniper Networks Junos OS allows an unauthenticated attacker to elevate their privileges over the target system through opportunistic use of an authenticated users session. This issue affects: Juniper Networks Junos OS 12.3 versions prior to 12.3R12-S17; 17.3 versions prior to 17.3R3-S10; 17.4 versions prior to 17.4R2-S12, 17.4R3-S3; 18.1 versions prior to 18.1R3-S11; 18.2 versions prior to 18.2R3-S6; 18.3 versions prior to 18.3R2-S4, 18.3R3-S4; 18.4 versions prior to 18.4R2-S5, 18.4R3-S5; 19.1 versions prior to 19.1R1-S6, 19.1R2-S2, 19.1R3-S3; 19.2 versions prior to 19.2R1-S5, 19.2R3, 19.2R3-S1; 19.3 versions prior to 19.3R2-S4, 19.3R3; 19.4 versions prior to 19.4R1-S3, 19.4R2-S2, 19.4R3; 20.1 versions prior to 20.1R1-S4, 20.1R2; 20.2 versions prior to 20.2R1-S1, 20.2R2.

Affected

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

Junos · Juniper Networks

95%

12.3 ≤ v < 12.3R12-S1717.3 ≤ v < 17.3R3-S1017.4 ≤ v < 17.4R2-S12, 17.4R3-S318.1 ≤ v < 18.1R3-S1118.2 ≤ v < 18.2R3-S618.3 ≤ v < 18.3R2-S4, 18.3R3-S418.4 ≤ v < 18.4R2-S5, 18.4R3-S519.1 ≤ v < 19.1R1-S6, 19.1R2-S2, 19.1R3-S319.2 ≤ v < 19.2R1-S5, 19.2R3, 19.2R3-S119.3 ≤ v < 19.3R2-S4, 19.3R319.4 ≤ v < 19.4R1-S3, 19.4R2-S2, 19.4R320.1 ≤ v < 20.1R1-S4, 20.1R220.2 ≤ v < 20.2R1-S1, 20.2R212.3 12.3 r1 12.3 r10 12.3 r10-s1 12.3 r10-s2 12.3 r11 12.3 r12 12.3 r12-s1 12.3 r12-s11 12.3 r12-s12 12.3 r12-s13 12.3 r12-s14 12.3 r12-s15 12.3 r12-s16 12.3 r12-s3 12.3 r12-s4 12.3 r12-s6 12.3 r12-s8 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 r2-s5 17.3 r3 17.3 r3-s1 17.3 r3-s2 17.3 r3-s3 17.3 r3-s4 17.3 r3-s7 17.3 r3-s8 17.3 r3-s9 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-s11 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 r2-s9 17.4 r3 17.4 r3-s1 17.4 r3-s2 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-s10 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 r2-s6 18.2 r3 18.2 r3-s1 18.2 r3-s2 18.2 r3-s3 18.2 r3-s4 18.2 r3-s5 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 18.3 r3-s2 18.3 r3-s3 18.4 18.4 r1 18.4 r1-s1 18.4 r1-s2 18.4 r1-s5 18.4 r1-s6 18.4 r2 18.4 r2-s1 18.4 r2-s2 18.4 r2-s3 18.4 r2-s4 18.4 r3 18.4 r3-s1 18.4 r3-s2 18.4 r3-s3 18.4 r3-s4 19.1 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 r2 19.1 r2-s1 19.1 r3 19.1 r3-s1 19.1 r3-s2 19.2 19.2 r1 19.2 r1-s1 19.2 r1-s2 19.2 r1-s3 19.2 r1-s4 19.3 19.3 r1 19.3 r1-s1 19.3 r2 19.3 r2-s1 19.3 r2-s2 19.3 r2-s3 19.4 19.4 r1 19.4 r1-s1 19.4 r1-s2 19.4 r2 19.4 r2-s1 20.1 20.1 r1 20.1 r1-s1 20.1 r1-s2 20.1 r1-s3 20.2 20.2 r1

Affected range stops below 12.3R12-S17, so it looks safe — our inference, not a vendor statement

Affected range stops below 17.3R3-S10, so it looks safe — our inference, not a vendor statement

Affected range stops below 17.4R2-S12, 17.4R3-S3, so it looks safe — our inference, not a vendor statement

Affected range stops below 18.1R3-S11, so it looks safe — our inference, not a vendor statement

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

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

Affected range stops below 18.4R2-S5, 18.4R3-S5, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.1R1-S6, 19.1R2-S2, 19.1R3-S3, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.2R1-S5, 19.2R3, 19.2R3-S1, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.3R2-S4, 19.3R3, so it looks safe — our inference, not a vendor statement

Affected range stops below 19.4R1-S3, 19.4R2-S2, 19.4R3, so it looks safe — our inference, not a vendor statement

Affected range stops below 20.1R1-S4, 20.1R2, so it looks safe — our inference, not a vendor statement

Affected range stops below 20.2R1-S1, 20.2R2, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references

https://kb.juniper.net/JSA11100

References (1)

x_refsource_CONFIRMVendor Advisory

Source: [email protected]

https://kb.juniper.net/JSA11100

CVSS

6.8MEDIUMjuniper

Attack Vector: NETWORK
Complexity: HIGH
Privileges: NONE
User Interaction: REQUIRED
Scope: UNCHANGED
Confidentiality: HIGH
Integrity: HIGH
Availability: NONE

Vector?

Quick Info

StatusMODIFIED

CWE

CWE-200

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