CVE-2021-31386
Last modified
CVE-2021-31386 is a medium-severity vulnerability rated 5.9/10 on the CVSS scale. 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.. EPSS estimates a 0.69% chance of exploitation in the next 30 days.
Description
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.
Metrics
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
Weakness Enumeration
Affected Software
| Vendor | Product | Versions | Update |
|---|---|---|---|
| Juniper | Junos | 12.3 | — |
| Juniper | Junos | 15.1 | — |
| Juniper | Junos | 18.3 | — |
| Juniper | Junos | 18.4 | — |
| Juniper | Junos | 19.1 | — |
| Juniper | Junos | 19.2 | — |
| Juniper | Junos | 19.3 | — |
| Juniper | Junos | 19.4 | R1 |
| Juniper | Junos | 20.1 | R1 |
| Juniper | Junos | 20.2 | R1 |
| Juniper | Junos | 20.3 | R1 |
| Juniper | Junos | 20.4 | R1 |
| Juniper | Junos | 21.1 | R1 |
| Juniper | Junos | 21.2 | R1 |
References
- https://kb.juniper.net/JSA11254Vendor Advisory
- https://kb.juniper.net/JSA11254Vendor Advisory
Timeline
- Published
- Last Modified
- Status
- Modified
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