medium
5.9
CWE
300 311 325 693
Advisory Published
Updated

CVE-2021-31386: Junos OS: When using J-Web with HTTP an attacker may retrieve encryption keys via Person-in-the-Middle attacks.

First published: Tue Oct 19 2021(Updated: )

A Protection Mechanism Failure vulnerability in the J-Web HTTP service of Juniper Networks Junos OS allows a remote unauthenticated attacker to perform Person-in-the-Middle (PitM) attacks against the device. This issue affects: Juniper Networks Junos OS 12.3 versions prior to 12.3R12-S20; 15.1 versions prior to 15.1R7-S11; 18.3 versions prior to 18.3R3-S6; 18.4 versions prior to 18.4R3-S10; 19.1 versions prior to 19.1R3-S7; 19.2 versions prior to 19.2R3-S4; 19.3 versions prior to 19.3R3-S4; 19.4 versions prior to 19.4R3-S6; 20.1 versions prior to 20.1R3-S2; 20.2 versions prior to 20.2R3-S3; 20.3 versions prior to 20.3R3-S1; 20.4 versions prior to 20.4R3; 21.1 versions prior to 21.1R3; 21.2 versions prior to 21.2R2.

Credit: sirt@juniper.net

Affected SoftwareAffected VersionHow to fix
Juniper JUNOS=12.3
Juniper JUNOS=12.3-r1
Juniper JUNOS=12.3-r10
Juniper JUNOS=12.3-r10-s1
Juniper JUNOS=12.3-r10-s2
Juniper JUNOS=12.3-r11
Juniper JUNOS=12.3-r12
Juniper JUNOS=12.3-r12-s1
Juniper JUNOS=12.3-r12-s10
Juniper JUNOS=12.3-r12-s11
Juniper JUNOS=12.3-r12-s12
Juniper JUNOS=12.3-r12-s13
Juniper JUNOS=12.3-r12-s14
Juniper JUNOS=12.3-r12-s15
Juniper JUNOS=12.3-r12-s16
Juniper JUNOS=12.3-r12-s17
Juniper JUNOS=12.3-r12-s18
Juniper JUNOS=12.3-r12-s19
Juniper JUNOS=12.3-r12-s3
Juniper JUNOS=12.3-r12-s4
Juniper JUNOS=12.3-r12-s6
Juniper JUNOS=12.3-r12-s8
Juniper JUNOS=12.3-r2
Juniper JUNOS=12.3-r3
Juniper JUNOS=12.3-r4
Juniper JUNOS=12.3-r5
Juniper JUNOS=12.3-r6
Juniper JUNOS=12.3-r7
Juniper JUNOS=12.3-r8
Juniper JUNOS=12.3-r9
Juniper JUNOS=15.1
Juniper JUNOS=15.1-a1
Juniper JUNOS=15.1-f
Juniper JUNOS=15.1-f1
Juniper JUNOS=15.1-f2
Juniper JUNOS=15.1-f2-s1
Juniper JUNOS=15.1-f2-s2
Juniper JUNOS=15.1-f2-s3
Juniper JUNOS=15.1-f2-s4
Juniper JUNOS=15.1-f3
Juniper JUNOS=15.1-f4
Juniper JUNOS=15.1-f5
Juniper JUNOS=15.1-f5-s7
Juniper JUNOS=15.1-f6
Juniper JUNOS=15.1-f6-s1
Juniper JUNOS=15.1-f6-s10
Juniper JUNOS=15.1-f6-s12
Juniper JUNOS=15.1-f6-s2
Juniper JUNOS=15.1-f6-s3
Juniper JUNOS=15.1-f6-s4
Juniper JUNOS=15.1-f6-s5
Juniper JUNOS=15.1-f6-s6
Juniper JUNOS=15.1-f6-s7
Juniper JUNOS=15.1-f6-s8
Juniper JUNOS=15.1-f6-s9
Juniper JUNOS=15.1-f7
Juniper JUNOS=15.1-r
Juniper JUNOS=15.1-r1
Juniper JUNOS=15.1-r2
Juniper JUNOS=15.1-r3
Juniper JUNOS=15.1-r4
Juniper JUNOS=15.1-r4-s7
Juniper JUNOS=15.1-r4-s8
Juniper JUNOS=15.1-r4-s9
Juniper JUNOS=15.1-r5
Juniper JUNOS=15.1-r5-s1
Juniper JUNOS=15.1-r5-s3
Juniper JUNOS=15.1-r5-s5
Juniper JUNOS=15.1-r5-s6
Juniper JUNOS=15.1-r6
Juniper JUNOS=15.1-r6-s1
Juniper JUNOS=15.1-r6-s2
Juniper JUNOS=15.1-r6-s3
Juniper JUNOS=15.1-r6-s4
Juniper JUNOS=15.1-r6-s6
Juniper JUNOS=15.1-r7
Juniper JUNOS=15.1-r7-s1
Juniper JUNOS=15.1-r7-s10
Juniper JUNOS=15.1-r7-s2
Juniper JUNOS=15.1-r7-s3
Juniper JUNOS=15.1-r7-s4
Juniper JUNOS=15.1-r7-s5
Juniper JUNOS=15.1-r7-s6
Juniper JUNOS=15.1-r7-s7
Juniper JUNOS=15.1-r7-s8
Juniper JUNOS=15.1-r7-s9
Juniper JUNOS=18.3
Juniper JUNOS=18.3-r1
Juniper JUNOS=18.3-r1-s1
Juniper JUNOS=18.3-r1-s2
Juniper JUNOS=18.3-r1-s3
Juniper JUNOS=18.3-r1-s4
Juniper JUNOS=18.3-r1-s5
Juniper JUNOS=18.3-r1-s6
Juniper JUNOS=18.3-r2
Juniper JUNOS=18.3-r2-s1
Juniper JUNOS=18.3-r2-s2
Juniper JUNOS=18.3-r2-s3
Juniper JUNOS=18.3-r2-s4
Juniper JUNOS=18.3-r3
Juniper JUNOS=18.3-r3-s1
Juniper JUNOS=18.3-r3-s2
Juniper JUNOS=18.3-r3-s3
Juniper JUNOS=18.3-r3-s4
Juniper JUNOS=18.3-r3-s5
Juniper JUNOS=18.4
Juniper JUNOS=18.4-r1
Juniper JUNOS=18.4-r1-s1
Juniper JUNOS=18.4-r1-s2
Juniper JUNOS=18.4-r1-s3
Juniper JUNOS=18.4-r1-s4
Juniper JUNOS=18.4-r1-s5
Juniper JUNOS=18.4-r1-s6
Juniper JUNOS=18.4-r1-s7
Juniper JUNOS=18.4-r2
Juniper JUNOS=18.4-r2-s1
Juniper JUNOS=18.4-r2-s2
Juniper JUNOS=18.4-r2-s3
Juniper JUNOS=18.4-r2-s4
Juniper JUNOS=18.4-r2-s5
Juniper JUNOS=18.4-r2-s6
Juniper JUNOS=18.4-r2-s7
Juniper JUNOS=18.4-r2-s8
Juniper JUNOS=18.4-r3
Juniper JUNOS=18.4-r3-s1
Juniper JUNOS=18.4-r3-s2
Juniper JUNOS=18.4-r3-s3
Juniper JUNOS=18.4-r3-s4
Juniper JUNOS=18.4-r3-s5
Juniper JUNOS=18.4-r3-s6
Juniper JUNOS=18.4-r3-s7
Juniper JUNOS=18.4-r3-s8
Juniper JUNOS=18.4-r3-s9
Juniper JUNOS=19.1
Juniper JUNOS=19.1-r1
Juniper JUNOS=19.1-r1-s1
Juniper JUNOS=19.1-r1-s2
Juniper JUNOS=19.1-r1-s3
Juniper JUNOS=19.1-r1-s4
Juniper JUNOS=19.1-r1-s5
Juniper JUNOS=19.1-r1-s6
Juniper JUNOS=19.1-r2
Juniper JUNOS=19.1-r2-s1
Juniper JUNOS=19.1-r2-s2
Juniper JUNOS=19.1-r3
Juniper JUNOS=19.1-r3-s1
Juniper JUNOS=19.1-r3-s2
Juniper JUNOS=19.1-r3-s3
Juniper JUNOS=19.1-r3-s4
Juniper JUNOS=19.1-r3-s5
Juniper JUNOS=19.1-r3-s6
Juniper JUNOS=19.2
Juniper JUNOS=19.2-r1
Juniper JUNOS=19.2-r1-s1
Juniper JUNOS=19.2-r1-s2
Juniper JUNOS=19.2-r1-s3
Juniper JUNOS=19.2-r1-s4
Juniper JUNOS=19.2-r1-s5
Juniper JUNOS=19.2-r1-s6
Juniper JUNOS=19.2-r2
Juniper JUNOS=19.2-r2-s1
Juniper JUNOS=19.2-r3
Juniper JUNOS=19.2-r3-s1
Juniper JUNOS=19.2-r3-s2
Juniper JUNOS=19.2-r3-s3
Juniper JUNOS=19.3
Juniper JUNOS=19.3-r1
Juniper JUNOS=19.3-r1-s1
Juniper JUNOS=19.3-r2
Juniper JUNOS=19.3-r2-s1
Juniper JUNOS=19.3-r2-s2
Juniper JUNOS=19.3-r2-s3
Juniper JUNOS=19.3-r2-s4
Juniper JUNOS=19.3-r2-s5
Juniper JUNOS=19.3-r3
Juniper JUNOS=19.3-r3-s1
Juniper JUNOS=19.3-r3-s2
Juniper JUNOS=19.3-r3-s3
Juniper JUNOS=19.4-r1
Juniper JUNOS=19.4-r1-s1
Juniper JUNOS=19.4-r1-s2
Juniper JUNOS=19.4-r1-s3
Juniper JUNOS=19.4-r2
Juniper JUNOS=19.4-r2-s1
Juniper JUNOS=19.4-r2-s2
Juniper JUNOS=19.4-r2-s3
Juniper JUNOS=19.4-r2-s4
Juniper JUNOS=19.4-r3
Juniper JUNOS=19.4-r3-s1
Juniper JUNOS=19.4-r3-s2
Juniper JUNOS=19.4-r3-s3
Juniper JUNOS=19.4-r3-s4
Juniper JUNOS=19.4-r3-s5
Juniper JUNOS=20.1-r1
Juniper JUNOS=20.1-r1-s1
Juniper JUNOS=20.1-r1-s2
Juniper JUNOS=20.1-r1-s3
Juniper JUNOS=20.1-r1-s4
Juniper JUNOS=20.1-r2
Juniper JUNOS=20.1-r2-s1
Juniper JUNOS=20.1-r3
Juniper JUNOS=20.1-r3-s1
Juniper JUNOS=20.2-r1
Juniper JUNOS=20.2-r1-s1
Juniper JUNOS=20.2-r1-s2
Juniper JUNOS=20.2-r1-s3
Juniper JUNOS=20.2-r2
Juniper JUNOS=20.2-r2-s1
Juniper JUNOS=20.2-r2-s2
Juniper JUNOS=20.2-r2-s3
Juniper JUNOS=20.2-r3
Juniper JUNOS=20.2-r3-s1
Juniper JUNOS=20.2-r3-s2
Juniper JUNOS=20.3-r1
Juniper JUNOS=20.3-r1-s1
Juniper JUNOS=20.3-r2
Juniper JUNOS=20.3-r2-s1
Juniper JUNOS=20.3-r3
Juniper JUNOS=20.4-r1
Juniper JUNOS=20.4-r1-s1
Juniper JUNOS=20.4-r2
Juniper JUNOS=20.4-r2-s1
Juniper JUNOS=21.1-r1
Juniper JUNOS=21.1-r1-s1
Juniper JUNOS=21.1-r2
Juniper JUNOS=21.2-r1
Juniper JUNOS=21.2-r1-s1

Remedy

The following software releases have been updated to resolve this specific issue: 12.3R12-S20, 15.1R7-S11, 18.3R3-S6, 18.4R3-S10, 19.1R3-S7, 19.2R3-S4, 19.3R3-S4, 19.4R3-S6, 20.1R3-S2, 20.2R3-S3, 20.3R3-S1, 20.4R3, 21.1R3, 21.2R2, 21.3R1, and all subsequent releases. Note: Use of HTTP must also be discontinued.

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