Vulnerability-Lookup

GHSA-WCMX-9W9J-Q7PH

Vulnerability from github – Published: 2026-04-10 00:30 – Updated: 2026-04-10 00:30

Details

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.

Severity ?

6.5 (Medium)


                  
                    CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

7.1 (High)


                  
                    CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/AU:Y/RE:M

Show details on source website

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{
  "affected": [],
  "aliases": [
    "CVE-2026-33780"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-401"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-04-09T22:16:26Z",
    "severity": "HIGH"
  },
  "details": "A Missing Release of Memory after Effective Lifetime vulnerability in the\u00a0Layer 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).\n\n\n\nIn 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.\n\nUse the following command to monitor the memory consumption by l2ald:\n\nuser@device\u003e show system process extensive | match \"PID|l2ald\" \n\n\n\nThis issue affects:\n\nJunos OS:\n\n\n\n  *  all versions before 22.4R3-S5,\n  *  23.2 versions before 23.2R2-S3,\n  *  23.4 versions before 23.4R2-S4,\n  *  24.2 versions before 24.2R2;\n\n\n\n\nJunos OS Evolved:\n\n\n\n  *  all versions before 22.4R3-S5-EVO,\n  *  23.2 versions before 23.2R2-S3-EVO,\n  *  23.4 versions before 23.4R2-S4-EVO,\n  *  24.2 versions before 24.2R2-EVO.",
  "id": "GHSA-wcmx-9w9j-q7ph",
  "modified": "2026-04-10T00:30:29Z",
  "published": "2026-04-10T00:30:29Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-33780"
    },
    {
      "type": "WEB",
      "url": "https://kb.juniper.net/JSA107819"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:Y/R:X/V:X/RE:M/U:X",
      "type": "CVSS_V4"
    }
  ]
}

CVE-2026-33780 (GCVE-0-2026-33780)

Vulnerability from cvelistv5 – Published: 2026-04-09 21:29 – Updated: 2026-04-09 21:29

Title

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

Summary

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.

Severity ?

6.5 (Medium)


                        
                          CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

7.1 (High)


                        
                          CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/AU:Y/RE:M

CWE

CWE-401 - Missing Release of Memory after Effective Lifetime

Assigner

juniper

References

URL

Tags

https://kb.juniper.net/JSA107819

vendor-advisory

Impacted products

Vendor

Product

Version

Juniper Networks

Junos OS

Affected: 0 , < 22.4R3-S5 (semver)
Affected: 23.2 , < 23.2R2-S3 (semver)
Affected: 23.4 , < 23.4R2-S4 (semver)
Affected: 24.2 , < 24.2R2 (semver)

Juniper Networks

Junos OS Evolved

Affected: all version prior to , < 22.4R3-S5-EVO (semver)
Affected: 23.2 , < 23.2R2-S3-EVO (semver)
Affected: 23.4 , < 23.4R2-S4-EVO (semver)
Affected: 24.2 , < 24.2R2-EVO (semver)

Date Public ?

2026-04-08 16:00

Show details on NVD website

JSON

To clipboard

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  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Junos OS",
          "vendor": "Juniper Networks",
          "versions": [
            {
              "lessThan": "22.4R3-S5",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThan": "23.2R2-S3",
              "status": "affected",
              "version": "23.2",
              "versionType": "semver"
            },
            {
              "lessThan": "23.4R2-S4",
              "status": "affected",
              "version": "23.4",
              "versionType": "semver"
            },
            {
              "lessThan": "24.2R2",
              "status": "affected",
              "version": "24.2",
              "versionType": "semver"
            }
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          "versions": [
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              "status": "affected",
              "version": "all version prior to",
              "versionType": "semver"
            },
            {
              "lessThan": "23.2R2-S3-EVO",
              "status": "affected",
              "version": "23.2",
              "versionType": "semver"
            },
            {
              "lessThan": "23.4R2-S4-EVO",
              "status": "affected",
              "version": "23.4",
              "versionType": "semver"
            },
            {
              "lessThan": "24.2R2-EVO",
              "status": "affected",
              "version": "24.2",
              "versionType": "semver"
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      ],
      "configurations": [
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          "supportingMedia": [
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            }
          ],
          "value": "To be exposed to this issue the device must be configured for EVPN-MPLS. Refer to product documentation for how to configure EVPN-MPLS as there are different configuration options."
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              "value": "A Missing Release of Memory after Effective Lifetime vulnerability in the\u0026nbsp;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).\u003cbr\u003e\u003cbr\u003e\n\nIn 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.\u003cbr\u003e\u003cbr\u003eUse the following command to monitor the memory consumption by l2ald:\u003cbr\u003e\u003cbr\u003e\u003ctt\u003euser@device\u0026gt; show system process extensive | match \"PID|l2ald\"\u003c/tt\u003e \n\n\u003cbr\u003e\u003cbr\u003e\u003cp\u003eThis issue affects:\u003c/p\u003e\u003cp\u003eJunos OS:\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cul\u003e\u003cli\u003eall versions before 22.4R3-S5,\u003c/li\u003e\u003cli\u003e23.2 versions before 23.2R2-S3,\u003c/li\u003e\u003cli\u003e23.4 versions before 23.4R2-S4,\u003c/li\u003e\u003cli\u003e24.2 versions before 24.2R2;\u003c/li\u003e\u003c/ul\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eJunos OS Evolved:\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cul\u003e\u003cli\u003eall versions before 22.4R3-S5-EVO,\u003c/li\u003e\u003cli\u003e23.2 versions before 23.2R2-S3-EVO,\u003c/li\u003e\u003cli\u003e23.4 versions before 23.4R2-S4-EVO,\u003c/li\u003e\u003cli\u003e24.2 versions before 24.2R2-EVO.\u003c/li\u003e\u003c/ul\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003cbr\u003e\u003c/p\u003e"
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Sightings

Author	Source	Type	Date

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

GHSA-WCMX-9W9J-Q7PH

CVE-2026-33780 (GCVE-0-2026-33780)

Tags

Sightings

Nomenclature