# 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

> An unauthenticated attacker can cause a denial of service in Junos OS by triggering a memory leak via interface flaps or route churn.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 20 Jul 2022
- **Updated:** 17 Sep 2024
- **Also known as:** GHSA-2jpc-grxp-p4w8

## What is CVE-2022-22209?

CVE-2022-22209 is a high-severity denial of service vulnerability in Juniper Junos, published on 20 Jul 2022. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official 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.

Weakness: CWE-401 (Missing Release of Memory after Effective Lifetime)

## Which versions are affected by CVE-2022-22209?

It affects 1 product.


Products: Juniper Junos.

## How do I fix CVE-2022-22209?

No fix has been published for CVE-2022-22209 yet. Limit exposure of the affected software until one is available.

## Is CVE-2022-22209 being exploited?

There is no known exploitation of CVE-2022-22209 in the wild and no public exploit code.

## Other vulnerabilities in Juniper Junos

- [CVE-2023-36845](https://insights.sbomify.com/CVE-2023-36845/): Juniper Junos OS EX Series and SRX Series PHP External Variable Modification (critical 9.8, exploited in the wild)
- [CVE-2020-1631](https://insights.sbomify.com/CVE-2020-1631/): Juniper Junos OS Path Traversal (high 8.8, exploited in the wild)
- [CVE-2025-21590](https://insights.sbomify.com/CVE-2025-21590/): Juniper Junos OS Improper Isolation or Compartmentalization (medium 6.7, exploited in the wild)
- [CVE-2023-36851](https://insights.sbomify.com/CVE-2023-36851/): Juniper Junos OS SRX Series Missing Authentication for Critical Function (medium 5.3, exploited in the wild)
- [CVE-2023-36844](https://insights.sbomify.com/CVE-2023-36844/): Juniper Junos OS EX Series PHP External Variable Modification (medium 5.3, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2022-22209 and fix it if it is affected.

What it is: CVE-2022-22209 is a high-severity denial of service vulnerability in Juniper Junos, published on 20 Jul 2022. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2022-22209 in the wild and no public exploit code.

Affected product: Juniper Junos. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2022-22209/ (Markdown: https://insights.sbomify.com/CVE-2022-22209/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-22209
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-22209
- OSV: https://osv.dev/vulnerability/CVE-2022-22209

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-22209/
Summaries are generated and may contain mistakes; the official description above is the record.