CVE-2021-31350Network attack vector

Root privilege escalation via unchecked configuration forwarding

Published Oct 19, 2021 · Updated Sep 16, 2024

Improper privilege management in Junos OS and Junos OS Evolved allows remote authenticated users to perform operations as root. The JET service daemon authenticates the user but forwards configuration operations directly to the root-running management daemon without enforcing the user's privileges. A low-privileged account with network access to the enabled gRPC service is sufficient to alter device configuration and completely compromise the system.

CVSS severity7.5
High
EPSS probability0.87%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper privilege management in Junos OS and Junos OS Evolved allows remote authenticated users to perform operations as root. The JET service daemon authenticates the user but forwards configuration operations directly to the root-running management daemon without enforcing the user's privileges. A low-privileged account with network access to the enabled gRPC service is sufficient to alter device configuration and completely compromise the system.

The record

CVE
CVE-2021-31350
Published
Oct 19, 2021
Updated
Sep 16, 2024
Vendor
Juniper Networks
Product
Junos OS Evolved
Classifications
CWE-269, T1068
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Oct 19, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=21.1-EVO <21.1R2-EVO
  2. Affected versionversion=unspecified <20.4R2-EVO

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Juniper Networks · Junos OS Evolvedversion=21.1-EVO <21.1R2-EVO; version=unspecified <20.4R2-EVO
Juniper Networks · Junos OSversion=18.4 <18.4R1-S8, 18.4R2-S8, 18.4R3-S8; version=19.1 <19.1R2-S3, 19.1R3-S5; version=19.2 <19.2R1-S7, 19.2R3-S2; version=19.3 <19.3R2-S6, 19.3R3-S2; version=19.4 <19.4R1-S4, 19.4R2-S4, 19.4R3-S3; version=20.1 <20.1R2-S2, 20.1R3; version=20.2 <20.2R2-S3, 20.2R3; version=20.3 <20.3R2-S1, 20.3R3; version=20.4 <20.4R2

Published CVSS scores

9.0NIST NVDAV:N/AC:L/Au:S/C:C/I:C/A:C
8.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
7.5Juniper Networks, Inc.CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-269Improper Privilege Management
T1068Exploitation for Privilege Escalation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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