CVE-2023-22406: Junos OS and Junos OS Evolved: A memory leak which will ultimately lead to an rpd crash will be observed when a peer interface flaps continuously in a Segment Routing scenario using OSPF

Severity: medium (CVSS 6.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2023-01-13 · updated 2026-06-17
Weakness: CWE-401

Description

A Missing Release of Memory after Effective Lifetime vulnerability in the kernel of Juniper Networks Junos OS and Junos OS Evolved allows an adjacent, unauthenticated attacker to cause a Denial of Service (DoS). In a segment-routing scenario with OSPF as IGP, when a peer interface continuously flaps, next-hop churn will happen and a continuous increase in Routing Protocol Daemon (rpd) memory consumption will be observed. This will eventually lead to an rpd crash and restart when the memory is full. The memory consumption can be monitored using the CLI command "show task memory detail" as shown in the following example: user@host> show task memory detail | match "RT_NEXTHOPS_TEMPLATE|RT_TEMPLATE_BOOK_KEE" RT_NEXTHOPS_TEMPLATE 1008 1024 T 50 51200 50 51200 RT_NEXTHOPS_TEMPLATE 688 768 T 50 38400 50 38400 RT_NEXTHOPS_TEMPLATE 368 384 T 412330 158334720 412330 158334720 RT_TEMPLATE_BOOK_KEE 2064 2560 T 33315 85286400 33315 85286400 user@host> show task memory detail | match "RT_NEXTHOPS_TEMPLATE|RT_TEMPLATE_BOOK_KEE" RT_NEXTHOPS_TEMPLATE 1008 1024 T 50 51200 50 51200 RT_NEXTHOPS_TEMPLATE 688 768 T 50 38400 50 38400 RT_NEXTHOPS_TEMPLATE 368 384 T 419005 160897920 419005 160897920 <=== RT_TEMPLATE_BOOK_KEE 2064 2560 T 39975 102336000 39975 10233600 <=== This issue affects: Juniper Networks Junos OS All versions prior to 19.3R3-S7; 19.4 versions prior to 19.4R2-S8, 19.4R3-S9; 20.2 versions prior to 20.2R3-S5; 20.3 versions prior to 20.3R3-S5; 20.4 versions prior to 20.4R3-S4; 21.1 versions prior to 21.1R3-S3; 21.2 versions prior to 21.2R3-S2; 21.3 versions prior to 21.3R3-S1; 21.4 versions prior to 21.4R2-S1, 21.4R3; 22.1 versions prior to 22.1R2. Juniper Networks Junos OS Evolved All versions prior to 20.4R3-S4-EVO; 21.4 versions prior to 21.4R2-S1-EVO, 21.4R3-EVO; 22.1 versions prior to 22.1R2-EVO.

Affected products

Juniper Junos OS: before 19.3; 19.3, 19.3-r1, 19.3-r1-s1, 19.3-r2, 19.3-r2-s1, 19.3-r2-s2 (+102) — fixed in 19.3
Juniper Networks Junos OS Evolved: before 20.4; 20.4, 20.4-r1, 20.4-r1-s1, 20.4-r1-s2, 20.4-r2, 20.4-r2-s1 (+14) — fixed in 20.4

How to fix

Upgrade to a fixed version: Juniper Junos OS 19.3; Juniper Networks Junos OS Evolved 20.4. Check the vendor advisory for mitigations.

References

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