CVE-2022-22172

CVE-2022-22172 is a medium-severity vulnerability in Juniper Junos with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-401.

Key facts

Description

A Missing Release of Memory after Effective Lifetime vulnerability in the Layer-2 control protocols daemon (l2cpd) of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated adjacent attacker to cause a memory leak. Continued exploitation can lead to memory exhaustion and thereby a Denial of Service (DoS). This issue occurs when specific LLDP packets are received. The impact of the l2cpd cores is that if any of the stp protocols (rstp, mstp or vstp) is used then stp re-converges and traffic loss will occur during that time. Also if any services depend on LLDP state (like PoE or VoIP device recognition) then these will also be affected. The memory utilization of the L2CPd process can be monitored with the following command: user@host> show system processes extensive | match l2cpd 1234 root 52 0 521M 43412K RUN 1 4:02 34.47% l2cpd This issue affects: Juniper Networks Junos OS 18.4 version 18.4R2-S4 and later versions prior to 18.4R2-S10. 19.2 versions prior to 19.2R1-S8, 19.2R3-S4; 19.3 versions prior to 19.3R3-S5; 19.4 versions prior to 19.4R3-S7; 20.1 versions prior to 20.1R3-S3; 20.2 versions prior to 20.2R3-S2; 20.3 versions prior to 20.3R3-S1; 20.4 versions prior to 20.4R3; 21.1 versions prior to 21.1R2-S2, 21.1R3; 21.2 versions prior to 21.2R2; Juniper Networks Junos OS Evolved All versions prior to 20.4R3-S2-EVO; 21.1 version 21.1R1-EVO and later versions; 21.2 versions prior to 21.2R2-EVO. This issue does not affect: Juniper Networks Junos OS 19.1 version 19.1R1 and later versions.

Frequently asked questions

What is CVE-2022-22172?
A Missing Release of Memory after Effective Lifetime vulnerability in the Layer-2 control protocols daemon (l2cpd) of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated adjacent attacker to cause a memory leak. Continued exploitation can lead to memory exhaustion and thereby a Denial of Service (DoS). This issue occurs when specific LLDP packets are received. The impact of the l2cpd cores is that if any of the stp protocols (rstp, mstp or vstp) is used then stp re-converges and traffic loss will occur during that time. Also if any services depend on LLDP state (like PoE or VoIP device recognition) then these will also be affected. The memory utilization of the L2CPd process can be monitored with the following command: user@host> show system processes extensive | match l2cpd 1234 root 52 0 521M 43412K RUN 1 4:02 34.47% l2cpd This issue affects: Juniper Networks Junos OS 18.4 version 18.4R2-S4 and later versions prior to 18.4R2-S10. 19.2 versions prior to 19.2R1-S8, 19.2R3-S4; 19.3 versions prior to 19.3R3-S5; 19.4 versions prior to 19.4R3-S7; 20.1 versions prior to 20.1R3-S3; 20.2 versions prior to 20.2R3-S2; 20.3 versions prior to 20.3R3-S1; 20.4 versions prior to 20.4R3; 21.1 versions prior to 21.1R2-S2, 21.1R3; 21.2 versions prior to 21.2R2; Juniper Networks Junos OS Evolved All versions prior to 20.4R3-S2-EVO; 21.1 version 21.1R1-EVO and later versions; 21.2 versions prior to 21.2R2-EVO. This issue does not affect: Juniper Networks Junos OS 19.1 version 19.1R1 and later versions.
How severe is CVE-2022-22172?
CVE-2022-22172 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2022-22172 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (29th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2022-22172?
CVE-2022-22172 primarily affects Juniper Junos. In total, 109 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2022-22172?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2022-22172 published?
CVE-2022-22172 was published on 2022-01-19 and last updated on 2026-06-17.

References

Affected products (109)

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