CVE-2021-0255: Junos OS: ethtraceroute Local Privilege Escalation vulnerability in SUID binaries

Severity: high (CVSS 7.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-04-22 · updated 2026-06-17
Weakness: CWE-250

Description

A local privilege escalation vulnerability in ethtraceroute of Juniper Networks Junos OS may allow a locally authenticated user with shell access to escalate privileges and write to the local filesystem as root. ethtraceroute is shipped with setuid permissions enabled and is owned by the root user, allowing local users to run ethtraceroute with root privileges. This issue affects Juniper Networks Junos OS: 15.1X49 versions prior to 15.1X49-D240; 17.3 versions prior to 17.3R3-S11, 17.4 versions prior to 17.4R3-S4; 18.1 versions prior to 18.1R3-S12; 18.2 versions prior to 18.2R3-S7; 18.3 versions prior to 18.3R3-S4; 18.4 versions prior to 18.4R2-S7; 19.1 versions prior to 19.1R1-S6, 19.1R2-S2, 19.1R3-S4; 19.3 versions prior to 19.3R3-S2; 19.4 versions prior to 19.4R3-S1; 20.1 versions prior to 20.1R2, 20.1R3; 20.2 versions prior to 20.2R2-S1, 20.2R3; 20.3 versions prior to 20.3R1-S1.

Affected products

Juniper Junos OS: 17.3, 17.3-r1, 17.3-r1-s1, 17.3-r1-s4, 17.3-r2, 17.3-r2-s1 (+176)

References

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