CVE-2021-0223

Junos OS: telnetd.real Local Privilege Escalation vulnerabilities in SUID binaries

Published Jan 15, 2021 CVSS 3.1 · 7.8 High EPSS < 1% KEV · Not listed
Description
A local privilege escalation vulnerability in telnetd.real of Juniper Networks Junos OS may allow a locally authenticated shell user to escalate privileges and execute arbitrary commands as root. telnetd.real is shipped with setuid permissions enabled and is owned by the root user, allowing local users to run telnetd.real with root privileges. This issue affects Juniper Networks Junos OS: all versions prior to 15.1R7-S9; 17.3 versions prior to 17.3R3-S11; 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-S7, 18.4R3-S6; 19.1 versions prior to 19.1R2-S2, 19.1R3-S4; 19.2 versions prior to 19.2R1-S6, 19.2R3-S1; 19.3 versions prior to 19.3R3-S1; 19.4 versions prior to 19.4R2-S2, 19.4R3; 20.1 versions prior to 20.1R1-S4, 20.1R2; 20.2 versions prior to 20.2R2.

Analysis

No analysis available yet

Remediation

Vendor Solution

The following software releases have been updated to resolve this specific issue: Junos OS 15.1R7-S9*, 17.3R3-S11*, 17.4R2-S12, 17.4R3-S3, 18.1R3-S11, 18.2R3-S6, 18.3R2-S4, 18.3R3-S4, 18.4R2-S7, 18.4R3-S6, 19.1R2-S2, 19.1R3-S4, 19.2R1-S6, 19.2R3-S1, 19.3R3-S1, 19.4R2-S2, 19.4R3, 20.1R1-S4, 20.1R2, 20.2R2, 20.3R1, and all subsequent releases. *Late availability


Vendor Workaround

Use access lists or firewall filters to limit CLI access to the device only from trusted, administrative networks or hosts. Limit access to the Junos OS shell to only trusted system administrators.

Tracking

Sign in to view the affected projects.

Advisories

Source ID Title
EUVD EUVD EUVD-2021-2842 A local privilege escalation vulnerability in telnetd.real of Juniper Networks Junos OS may allow a locally authenticated shell user to escalate privileges and execute arbitrary commands as root. telnetd.real is shipped with setuid permissions enabled and is owned by the root user, allowing local users to run telnetd.real with root privileges. This issue affects Juniper Networks Junos OS: all versions prior to 15.1R7-S9; 17.3 versions prior to 17.3R3-S11; 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-S7, 18.4R3-S6; 19.1 versions prior to 19.1R2-S2, 19.1R3-S4; 19.2 versions prior to 19.2R1-S6, 19.2R3-S1; 19.3 versions prior to 19.3R3-S1; 19.4 versions prior to 19.4R2-S2, 19.4R3; 20.1 versions prior to 20.1R1-S4, 20.1R2; 20.2 versions prior to 20.2R2.
References
History

No history.

Weaknesses
  • CWE-250

    Execution with Unnecessary Privileges

  • CWE-269

    Improper Privilege Management

Sources

Status
PUBLISHED
Assigner
juniper
Published
Updated
Sep 17, 2024, 12:46 AM
Reserved
Oct 27, 2020, 12:00 AM
Status
Modified
Published
Jan 15, 2021, 6:15 PM
Modified
Jun 17, 2026, 3:29 AM