CyberSecBulletin
CVE-2022-22239NVD status: Modified

Junos OS Evolved: Improper Privilege Management

CVE-2022-22239 is a high-severity improper privilege management vulnerability in Junos OS Evolved from Juniper Networks, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists versions 20.4R3-S5-EVO, 21.1R3-EVO, 21.2R2-S1-EVO, 21.2R3-EVO as the first without the flaw, so updating Junos OS Evolved to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.19% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Junos OS Evolved to 20.4R3-S5-EVO or 21.1R3-EVO or 21.2R2-S1-EVO, 21.2R3-EVO or 21.3R2-EVO, whichever matches your release line, or a later version.
  2. Read the advisory on kb.juniper.net for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
Juniper NetworksJunos OS Evolvedbefore 20.4R3-S5-EVO; 21.1-EVO up to, but not including, 21.1R3-EVO; 21.2-EVO up to, but not including, 21.2R2-S1-EVO, 21.2R3-EVO; 21.3-EVO up to, but not including, 21.3R2-EVO20.4R3-S5-EVO, 21.1R3-EVO, 21.2R2-S1-EVO, 21.2R3-EVO, 21.3R2-EVO

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
ChangedThe attack can reach beyond the vulnerable component into other systems.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.18.2HighCNA (juniper.net)
CVSS 3.18.8HighNVD

Official description

An Execution with Unnecessary Privileges vulnerability in Management Daemon (mgd) of Juniper Networks Junos OS Evolved allows a locally authenticated attacker with low privileges to escalate their privileges on the device and potentially remote systems. This vulnerability allows a locally authenticated attacker with access to the ssh operational command to escalate their privileges on the system to root, or if there is user interaction on the local device to potentially escalate privileges on a remote system to root. This issue affects Juniper Networks Junos OS Evolved: All versions prior to 20.4R3-S5-EVO; 21.1-EVO versions prior to 21.1R3-EVO; 21.2-EVO versions prior to 21.2R2-S1-EVO, 21.2R3-EVO; 21.3-EVO versions prior to 21.3R2-EVO. This issue does not affect Juniper Networks Junos OS.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Privilege Management

The product does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for that actor.

How developers prevent this class of flaw

  • Very carefully manage the setting, management, and handling of privileges. Explicitly manage trust zones in the software.
  • Follow the principle of least privilege when assigning access rights to entities in a software system.
  • Consider following the principle of separation of privilege. Require multiple conditions to be met before permitting access to a system resource.

More Improper Privilege Management vulnerabilities (CWE-269)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in Junos OS Evolved

All Junos OS Evolved vulnerabilities

Recent Improper Privilege Management vulnerabilities

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