Vulnerability-Lookup

FKIE_CVE-2026-33780

Vulnerability from fkie_nvd - Published: 2026-04-09 22:16 - Updated: 2026-04-09 22:16

Severity ?

6.5 (Medium) - CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

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.

References

	URL	Tags
	sirt@juniper.net	https://kb.juniper.net/JSA107819

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "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": "CVE-2026-33780",
  "lastModified": "2026-04-09T22:16:26.960",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "ADJACENT_NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 6.5,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 3.6,
        "source": "sirt@juniper.net",
        "type": "Primary"
      }
    ],
    "cvssMetricV40": [
      {
        "cvssData": {
          "Automatable": "YES",
          "Recovery": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "attackComplexity": "LOW",
          "attackRequirements": "NONE",
          "attackVector": "ADJACENT",
          "availabilityRequirement": "NOT_DEFINED",
          "baseScore": 7.1,
          "baseSeverity": "HIGH",
          "confidentialityRequirement": "NOT_DEFINED",
          "exploitMaturity": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "privilegesRequired": "NONE",
          "providerUrgency": "NOT_DEFINED",
          "subAvailabilityImpact": "LOW",
          "subConfidentialityImpact": "NONE",
          "subIntegrityImpact": "NONE",
          "userInteraction": "NONE",
          "valueDensity": "NOT_DEFINED",
          "vectorString": "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",
          "version": "4.0",
          "vulnAvailabilityImpact": "HIGH",
          "vulnConfidentialityImpact": "NONE",
          "vulnIntegrityImpact": "NONE",
          "vulnerabilityResponseEffort": "MODERATE"
        },
        "source": "sirt@juniper.net",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-04-09T22:16:26.960",
  "references": [
    {
      "source": "sirt@juniper.net",
      "url": "https://kb.juniper.net/JSA107819"
    }
  ],
  "sourceIdentifier": "sirt@juniper.net",
  "vulnStatus": "Received",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-401"
        }
      ],
      "source": "sirt@juniper.net",
      "type": "Primary"
    }
  ]
}

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

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

{
  "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"
            }
          ]
        },
        {
          "defaultStatus": "unaffected",
          "product": "Junos OS Evolved",
          "vendor": "Juniper Networks",
          "versions": [
            {
              "lessThan": "22.4R3-S5-EVO",
              "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"
            }
          ]
        }
      ],
      "configurations": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "\u003cspan style=\"background-color: rgb(251, 251, 251);\"\u003eTo 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.\u003c/span\u003e\n\n\u003cbr\u003e"
            }
          ],
          "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."
        }
      ],
      "datePublic": "2026-04-08T16:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "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"
            }
          ],
          "value": "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."
        }
      ],
      "exploits": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "Juniper SIRT is not aware of any malicious exploitation of this vulnerability."
            }
          ],
          "value": "Juniper SIRT is not aware of any malicious exploitation of this vulnerability."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "ADJACENT_NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 6.5,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "NONE",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
            "version": "3.1"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        },
        {
          "cvssV4_0": {
            "Automatable": "YES",
            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "ADJACENT",
            "baseScore": 7.1,
            "baseSeverity": "HIGH",
            "privilegesRequired": "NONE",
            "providerUrgency": "NOT_DEFINED",
            "subAvailabilityImpact": "LOW",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "valueDensity": "NOT_DEFINED",
            "vectorString": "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",
            "version": "4.0",
            "vulnAvailabilityImpact": "HIGH",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "NONE",
            "vulnerabilityResponseEffort": "MODERATE"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "problemTypes": [
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          "descriptions": [
            {
              "cweId": "CWE-401",
              "description": "CWE-401 Missing Release of Memory after Effective Lifetime",
              "lang": "en",
              "type": "CWE"
            }
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        }
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      "providerMetadata": {
        "dateUpdated": "2026-04-09T21:29:20.534Z",
        "orgId": "8cbe9d5a-a066-4c94-8978-4b15efeae968",
        "shortName": "juniper"
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      "references": [
        {
          "tags": [
            "vendor-advisory"
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          "url": "https://kb.juniper.net/JSA107819"
        }
      ],
      "solutions": [
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          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "The following software releases have been updated to resolve this specific issue: \u003cbr\u003eJunos OS Evolved: 22.4R3-S5-EVO, 23.2R2-S3-EVO, 23.4R2-S4-EVO, 24.2R2-EVO, 24.4R1-EVO,\u0026nbsp;and all subsequent releases;\u003cbr\u003eJunos OS: 22.4R3-S5, 23.2R2-S3, 23.4R2-S4, 24.2R2, 24.4R1, and all subsequent releases."
            }
          ],
          "value": "The following software releases have been updated to resolve this specific issue: \nJunos OS Evolved: 22.4R3-S5-EVO, 23.2R2-S3-EVO, 23.4R2-S4-EVO, 24.2R2-EVO, 24.4R1-EVO,\u00a0and all subsequent releases;\nJunos OS: 22.4R3-S5, 23.2R2-S3, 23.4R2-S4, 24.2R2, 24.4R1, and all subsequent releases."
        }
      ],
      "source": {
        "advisory": "JSA107819",
        "defect": [
          "1824956"
        ],
        "discovery": "USER"
      },
      "title": "Junos OS and Junos OS Evolved: In an EVPN-MPLS scenario churn of ESI routes causes a memory leak in l2ald",
      "workarounds": [
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          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "There are no known workarounds for this issue."
            }
          ],
          "value": "There are no known workarounds for this issue."
        }
      ],
      "x_generator": {
        "engine": "Vulnogram 0.1.0-dev"
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    }
  },
  "cveMetadata": {
    "assignerOrgId": "8cbe9d5a-a066-4c94-8978-4b15efeae968",
    "assignerShortName": "juniper",
    "cveId": "CVE-2026-33780",
    "datePublished": "2026-04-09T21:29:20.534Z",
    "dateReserved": "2026-03-23T19:46:13.669Z",
    "dateUpdated": "2026-04-09T21:29:20.534Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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

FKIE_CVE-2026-33780

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

Tags

Sightings

Nomenclature