CVE-2020-1625

Public Exploit
Junos OS: Kernel memory leak in virtual-memory due to interface flaps

Description

The kernel memory usage represented as "temp" via 'show system virtual-memory' may constantly increase when Integrated Routing and Bridging (IRB) is configured with multiple underlay physical interfaces, and one interface flaps. This memory leak can affect running daemons (processes), leading to an extended Denial of Service (DoS) condition. Usage of "temp" virtual memory, shown here by a constantly increasing value of outstanding Requests, can be monitored by executing the 'show system virtual-memory' command as shown below: user@junos> show system virtual-memory |match "fpc|type|temp" fpc0: -------------------------------------------------------------------------- Type InUse MemUse HighUse Requests Size(s) temp 2023 431K - 10551 16,32,64,128,256,512,1024,2048,4096,65536,262144,1048576,2097152,4194304,8388608 fpc1: -------------------------------------------------------------------------- Type InUse MemUse HighUse Requests Size(s) temp 2020 431K - 6460 16,32,64,128,256,512,1024,2048,4096,65536,262144,1048576,2097152,4194304,8388608 user@junos> show system virtual-memory |match "fpc|type|temp" fpc0: -------------------------------------------------------------------------- Type InUse MemUse HighUse Requests Size(s) temp 2023 431K - 16101 16,32,64,128,256,512,1024,2048,4096,65536,262144,1048576,2097152,4194304,8388608 fpc1: -------------------------------------------------------------------------- Type InUse MemUse HighUse Requests Size(s) temp 2020 431K - 6665 16,32,64,128,256,512,1024,2048,4096,65536,262144,1048576,2097152,4194304,8388608 user@junos> show system virtual-memory |match "fpc|type|temp" fpc0: -------------------------------------------------------------------------- Type InUse MemUse HighUse Requests Size(s) temp 2023 431K - 21867 16,32,64,128,256,512,1024,2048,4096,65536,262144,1048576,2097152,4194304,8388608 fpc1: -------------------------------------------------------------------------- Type InUse MemUse HighUse Requests Size(s) temp 2020 431K - 6858 16,32,64,128,256,512,1024,2048,4096,65536,262144,1048576,2097152,4194304,8388608 This issue affects Juniper Networks Junos OS: 16.1 versions prior to 16.1R7-S6; 17.1 versions prior to 17.1R2-S11, 17.1R3-S1; 17.2 versions prior to 17.2R2-S8, 17.2R3-S3; 17.2X75 versions prior to 17.2X75-D44; 17.3 versions prior to 17.3R2-S5, 17.3R3-S6; 17.4 versions prior to 17.4R2-S5, 17.4R3; 18.1 versions prior to 18.1R3-S7; 18.2 versions prior to 18.2R2-S5, 18.2R3; 18.2X75 versions prior to 18.2X75-D33, 18.2X75-D411, 18.2X75-D420, 18.2X75-D60; 18.3 versions prior to 18.3R1-S5, 18.3R2-S3, 18.3R3; 18.4 versions prior to 18.4R2-S2, 18.4R3; 19.1 versions prior to 19.1R1-S3, 19.1R2; 19.2 versions prior to 19.2R1-S3, 19.2R2. This issue does not affect Juniper Networks Junos OS 12.3 and 15.1.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: 16.1R7-S6, 17.1R2-S11, 17.1R3-S1, 17.2R2-S8, 17.2R3-S3, 17.2X75-D44, 17.3R2-S5, 17.3R3-S6, 17.4R2-S5, 17.4R3, 18.1R3-S7, 18.2R2-S5, 18.2R3, 18.2X75-D33, 18.2X75-D411, 18.2X75-D420, 18.2X75-D60, 18.3R1-S5, 18.3R2-S3, 18.3R3, 18.4R2-S2, 18.4R3, 19.1R1-S3, 19.1R2, 19.2R1-S3, 19.2R2, 19.3R1, and all subsequent releases.

Workaround:

  • There are no viable workarounds for this issue.

Categories

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.11%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Link Tags
https://kb.juniper.net/JSA11004 exploit vendor advisory

Frequently Asked Questions

What is the severity of CVE-2020-1625?
CVE-2020-1625 has been scored as a medium severity vulnerability.
How to fix CVE-2020-1625?
To fix CVE-2020-1625: The following software releases have been updated to resolve this specific issue: 16.1R7-S6, 17.1R2-S11, 17.1R3-S1, 17.2R2-S8, 17.2R3-S3, 17.2X75-D44, 17.3R2-S5, 17.3R3-S6, 17.4R2-S5, 17.4R3, 18.1R3-S7, 18.2R2-S5, 18.2R3, 18.2X75-D33, 18.2X75-D411, 18.2X75-D420, 18.2X75-D60, 18.3R1-S5, 18.3R2-S3, 18.3R3, 18.4R2-S2, 18.4R3, 19.1R1-S3, 19.1R2, 19.2R1-S3, 19.2R2, 19.3R1, and all subsequent releases.
Is CVE-2020-1625 being actively exploited in the wild?
It is possible that CVE-2020-1625 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2020-1625?
CVE-2020-1625 affects Juniper Networks Junos OS.
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