CVE-2021-31385

Junos OS: J-Web: A path traversal vulnerability allows an authenticated attacker to elevate their privileges to root

Description

An Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') vulnerability in J-Web of Juniper Networks Junos OS allows any low-privileged authenticated attacker to elevate their privileges to root. This issue affects: Juniper Networks Junos OS 12.3 versions prior to 12.3R12-S19; 15.1 versions prior to 15.1R7-S10; 18.3 versions prior to 18.3R3-S5; 18.4 versions prior to 18.4R3-S9; 19.1 versions prior to 19.1R3-S6; 19.2 versions prior to 19.2R1-S7, 19.2R3-S3; 19.3 versions prior to 19.3R3-S3; 19.4 versions prior to 19.4R3-S5; 20.1 versions prior to 20.1R2-S2, 20.1R3-S1; 20.2 versions prior to 20.2R3-S2; 20.3 versions prior to 20.3R3; 20.4 versions prior to 20.4R2-S1, 20.4R3; 21.1 versions prior to 21.1R1-S1, 21.1R2.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: 12.3R12-S19, 15.1R7-S10, 18.3R3-S5, 18.4R3-S9, 19.1R3-S6, 19.2R1-S7, 19.2R3-S3, 19.3R3-S3, 19.4R3-S5, 20.1R2-S2, 20.1R3-S1, 20.2R3-S2, 20.3R3, 20.4R2-S1, 20.4R3, 21.1R1-S1, 21.1R2, 21.2R1, and all subsequent releases.

Workaround:

  • There are no viable workarounds for these issues other than disabling J-Web. To reduce the risk of exploitation of these issues, use access lists or firewall filters to limit access to only trusted administrative networks, hosts and users.

Category

8.8
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.71% Top 30%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Link Tags
https://kb.juniper.net/JSA11253 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-31385?
CVE-2021-31385 has been scored as a high severity vulnerability.
How to fix CVE-2021-31385?
To fix CVE-2021-31385: The following software releases have been updated to resolve this specific issue: 12.3R12-S19, 15.1R7-S10, 18.3R3-S5, 18.4R3-S9, 19.1R3-S6, 19.2R1-S7, 19.2R3-S3, 19.3R3-S3, 19.4R3-S5, 20.1R2-S2, 20.1R3-S1, 20.2R3-S2, 20.3R3, 20.4R2-S1, 20.4R3, 21.1R1-S1, 21.1R2, 21.2R1, and all subsequent releases.
Is CVE-2021-31385 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-31385 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-31385?
CVE-2021-31385 affects Juniper Networks Junos OS, Juniper Networks Junos OS.
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