🔐 CVE Alert

CVE-2026-33780

MEDIUM 6.5

Junos OS and Junos OS Evolved: In an EVPN-MPLS scenario churn of ESI routes causes a memory leak in l2ald

CVSS Score
6.5
EPSS Score
0.0%
EPSS Percentile
4th

A Missing Release of Memory after Effective Lifetime vulnerability in the Layer 2 Address Learning Daemon (l2ald) of Juniper Networks Junos OS and Junos OS Evolved allows an adjacent, unauthenticated attacker to cause a memory leak ultimately leading to a Denial of Service (DoS). In an EVPN-MPLS scenario, routes learned from remote multi-homed Provider Edge (PE) devices are programmed as ESI routes. Due to a logic issue in the l2ald memory management, memory allocated for these routes is not released when there is churn for these routes. As a result, memory leaks in the l2ald process which will ultimately lead to a crash and restart of l2ald. Use the following command to monitor the memory consumption by l2ald: user@device> show system process extensive | match "PID|l2ald" This issue affects: Junos OS: * all versions before 22.4R3-S5, * 23.2 versions before 23.2R2-S3, * 23.4 versions before 23.4R2-S4, * 24.2 versions before 24.2R2; Junos OS Evolved: * all versions before 22.4R3-S5-EVO, * 23.2 versions before 23.2R2-S3-EVO, * 23.4 versions before 23.4R2-S4-EVO, * 24.2 versions before 24.2R2-EVO.

CWE CWE-401
Vendor juniper networks
Product junos os
Published Apr 9, 2026
Last Updated Apr 13, 2026
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CVSS v3 Breakdown

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack Vector
Adjacent
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

Affected Versions

Juniper Networks / Junos OS
0 < 22.4R3-S5 23.2 < 23.2R2-S3 23.4 < 23.4R2-S4 24.2 < 24.2R2
Juniper Networks / Junos OS Evolved
all version prior to < 22.4R3-S5-EVO 23.2 < 23.2R2-S3-EVO 23.4 < 23.4R2-S4-EVO 24.2 < 24.2R2-EVO

References

NVD ↗ CVE.org ↗ EPSS Data ↗
kb.juniper.net: https://kb.juniper.net/JSA107819