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

Description

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.

Scores

EPSS (exploitation in 30 days)

1.0% · top 36% of all CVEs (7 Nov 2026)

The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.5.

Weakness

• CWE-401 Improper Release of Memory Before Removing Last Reference (opens in a new tab)All about CWE-401 and its CVEs
• Denial of Service (DoS)

Affected products

• Juniper Networks · Junos OS

  • unaffected unspecified – < 21.2R1
  • affected 21.2 – < 21.2R3
  • affected 21.3 – < 21.3R2-S1, 21.3R3
  • affected 21.4 – < 21.4R1-S2, 21.4R2

What to do

Solution: The following software releases have been updated to resolve this specific issue: 21.2R3, 21.3R2-S1, 21.3R3, 21.4R1-S2, 21.4R2, 22.1R1, and all subsequent releases. Note: Only those releases listed in the PROBLEM section above are affected. This fix has also been proactively committed into other releases that are not vulnerable to this issue.

Workaround: There are no known workarounds for this issue.

References (1)

• https://kb.juniper.net/JSA69713 (opens in a new tab)x_refsource_CONFIRMx_transferred

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisories (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

[![CVE-2022-22209](https://trackcve.app/badge/CVE-2022-22209.svg)](https://trackcve.app/cve/CVE-2022-22209)

Record last updated 17 Sept 2024, 00:10 UTC.