CVE-2022-22172

Denial of service via l2cpd LLDP memory leak

Published Jan 19, 2022 · Updated Sep 16, 2024

Memory leakage in l2cpd in Juniper Networks Junos OS and Junos OS Evolved allows attackers to exhaust memory with crafted LLDP packets. The daemon fails to release memory after processing specific LLDP packets, so repeated packets steadily consume its available memory. Access to the device's Layer 2 network is required; exhaustion can core l2cpd, trigger STP reconvergence and traffic loss, and disrupt LLDP-dependent PoE or VoIP recognition.

CVSS severity6.5
Medium
EPSS probability0.37%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Memory leakage in l2cpd in Juniper Networks Junos OS and Junos OS Evolved allows attackers to exhaust memory with crafted LLDP packets. The daemon fails to release memory after processing specific LLDP packets, so repeated packets steadily consume its available memory. Access to the device's Layer 2 network is required; exhaustion can core l2cpd, trigger STP reconvergence and traffic loss, and disrupt LLDP-dependent PoE or VoIP recognition.

The record

CVE
CVE-2022-22172
Published
Jan 19, 2022
Updated
Sep 16, 2024
Vendor
Juniper Networks
Product
Junos OS Evolved
Classifications
CWE-401, T1499.004
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 19, 2022CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=21.1R1-EVO <21.1*
  2. Affected versionversion=21.2 <21.2R2-EVO
  3. Affected versionversion=unspecified <20.4R3-S2-EVO

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesunauthenticated

What is affected?

Juniper Networks · Junos OS Evolvedversion=21.1R1-EVO <21.1*; version=21.2 <21.2R2-EVO; version=unspecified <20.4R3-S2-EVO
Juniper Networks · Junos OSversion=18.4R2-S4 <18.4* changes=[{"at":"18.4R2-S10","status":"unaffected"}]; version=19.2 <19.2R1-S8, 19.2R3-S4; version=19.3 <19.3R3-S5; version=19.4 <19.4R3-S7; version=20.1 <20.1R3-S3; version=20.2 <20.2R3-S2; version=20.3 <20.3R3-S1; version=20.4 <20.4R3; version=21.1 <21.1R2-S2, 21.1R3; version=21.2 <21.2R2

Published CVSS scores

3.3NIST NVDAV:A/AC:L/Au:N/C:N/I:N/A:P
6.5Juniper Networks, Inc.CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectoradjacent
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-401Missing Release of Memory after Effective Lifetime
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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