CVE-2022-22209: Junos OS: RIB and PFEs can get out of sync due to a memory leak caused by interface flaps or route churn

First published: Wed Jul 20 2022(Updated: )

A Missing Release of Memory after Effective Lifetime vulnerability in the kernel of Juniper Networks Junos OS allows an unauthenticated network based attacker to cause a Denial of Service (DoS). On all Junos platforms, the Kernel Routing Table (KRT) queue can get stuck due to a memory leak triggered by interface flaps or route churn leading to RIB and PFEs getting out of sync. The memory leak causes RTNEXTHOP/route and next-hop memory pressure issue and the KRT queue will eventually get stuck with the error- 'ENOMEM -- Cannot allocate memory'. The out-of-sync state between RIB and FIB can be seen with the "show route" and "show route forwarding-table" command. This issue will lead to failures for adding new routes. The KRT queue status can be checked using the CLI command "show krt queue": user@host > show krt state High-priority add queue: 1 queued ADD nhtype Router index 0 (31212) error 'ENOMEM -- Cannot allocate memory' kqp '0x8ad5e40' The following messages will be observed in /var/log/messages, which indicate high memory for routes/nexthops: host rpd[16279]: RPD_RT_HWM_NOTICE: New RIB highwatermark for routes: 266 [2022-03-04 05:06:07] host rpd[16279]: RPD_KRT_Q_RETRIES: nexthop ADD: Cannot allocate memory host rpd[16279]: RPD_KRT_Q_RETRIES: nexthop ADD: Cannot allocate memory host kernel: rts_veto_net_delayed_unref_limit: Route/nexthop memory is severe pressure. User Application to perform recovery actions. O p 8 err 12, rtsm_id 0:-1, msg type 10, veto simulation: 0. host kernel: rts_veto_net_delayed_unref_limit: Memory usage of M_RTNEXTHOP type = (806321208) Max size possible for M_RTNEXTHOP type = (689432176) Current delayed unref = (0), Max delayed unref on this platform = (120000) Current delayed weight unref = (0) Max delayed weight unref on this platform = (400000) curproc = rpd. This issue affects: Juniper Networks Junos OS 21.2 versions prior to 21.2R3; 21.3 versions prior to 21.3R2-S1, 21.3R3; 21.4 versions prior to 21.4R1-S2, 21.4R2; This issue does not affect Juniper Networks Junos OS versions prior to 21.2R1.

Credit: sirt@juniper.net

Never miss a vulnerability like this again

Sign up to SecAlerts for real-time vulnerability data matched to your software, aggregated from hundreds of sources.

Read MoreStart Free Trial

• collector/nvd-index
• agent/type
• agent/softwarecombine
• collector/mitre-cve
• source/MITRE
• agent/remedy
• agent/severity
• agent/author
• agent/weakness
• agent/title
• agent/last-modified-date
• agent/references
• agent/tags
• agent/description
• agent/first-publish-date
• agent/event
• vendor/juniper
• canonical/juniper junos
• version/juniper junos/21.2
• version/juniper junos/21.2-r1
• version/juniper junos/21.2-r1-s1
• version/juniper junos/21.2-r1-s2
• version/juniper junos/21.2-r2
• version/juniper junos/21.2-r2-s1
• version/juniper junos/21.2-r2-s2
• version/juniper junos/21.3
• version/juniper junos/21.3-r1
• version/juniper junos/21.3-r1-s1
• version/juniper junos/21.3-r1-s2
• version/juniper junos/21.3-r2
• version/juniper junos/21.4
• version/juniper junos/21.4-r1
• version/juniper junos/21.4-r1-s1