CyberSecBulletin
CVE-2022-22170NVD status: Modified

Junos OS: Missing Release of Resource after Effective Lifetime

CVE-2022-22170 is a high-severity missing release of resource after effective lifetime vulnerability in Junos OS from Juniper Networks, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists versions 19.4R2-S6, 19.4R3-S6, 20.1R3-S2, 20.2R3-S3 as the first without the flaw, so updating Junos OS to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.96% chance of exploitation within 30 days, higher than 62% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Junos OS to 19.4R2-S6, 19.4R3-S6 or 20.1R3-S2 or 20.2R3-S3 or 20.3R3-S1, whichever matches your release line, or a later version.
  2. Read the advisory on kb.juniper.net for workarounds and exact fixed builds.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
Juniper NetworksJunos OS19.4 up to, but not including, 19.4R2-S6, 19.4R3-S6; 20.1 up to, but not including, 20.1R3-S2; 20.2 up to, but not including, 20.2R3-S3; 20.3 up to, but not including, 20.3R3-S1; 20.4 up to, but not including, 20.4R3; 21.1 up to, but not including, 21.1R3; 21.2 up to, but not including, 21.2R219.4R2-S6, 19.4R3-S6, 20.1R3-S2, 20.2R3-S3, 20.3R3-S1, 20.4R3, 21.1R3
Juniper NetworksJunos19.4; 20.1; 20.2; 20.3; 20.4; 21.1; 21.2; 21.3Not stated

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
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
NoneNo data is disclosed.
Integrity
NoneNothing can be modified.
Availability
HighThe component can be taken down completely.

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

Scoring systemScoreSeverityScored by
CVSS 3.17.5HighCNA (juniper.net)
CVSS 3.17.5HighNVD
CVSS 2.05.0MediumNVD

Official description

A Missing Release of Resource after Effective Lifetime vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS allows an unauthenticated networked attacker to cause a Denial of Service (DoS) by sending specific packets over VXLAN which cause heap memory to leak and on exhaustion the PFE to reset. The heap memory utilization can be monitored with the command: user@host> show chassis fpc This issue affects: Juniper Networks Junos OS 19.4 versions prior to 19.4R2-S6, 19.4R3-S6; 20.1 versions prior to 20.1R3-S2; 20.2 versions prior to 20.2R3-S3; 20.3 versions prior to 20.3R3-S1; 20.4 versions prior to 20.4R3; 21.1 versions prior to 21.1R3; 21.2 versions prior to 21.2R2. This issue does not affect versions of Junos OS prior to 19.4R1.

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

The underlying weakness: Missing Release of Resource after Effective Lifetime

The product does not release a resource after its effective lifetime has ended, i.e., after the resource is no longer needed.

How developers prevent this class of flaw

  • Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, languages such as Java, Ruby, and Lisp perform automatic garbage collection that releases memory for objects that have been deallocated.
  • It is good practice to be responsible for freeing all resources you allocate and to be consistent with how and where you free resources in a function. If you allocate resources that you intend to free upon completion of the function, you must be sure to free the resources at all exit points for that function including error conditions.

More Missing Release of Resource after Effective Lifetime vulnerabilities (CWE-772)

Timeline

  1. CVE record published.
  2. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in Junos OS

All Junos OS vulnerabilities

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