Vulnerability-Lookup

GHSA-GV4F-M3JW-J3H9

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

Details

On EX4k, and QFX5k platforms configured as service-provider edge devices, if L2PT is enabled on the UNI and VSTP is enabled on NNI in VXLAN scenarios, receiving VSTP BPDUs on UNI leads to packet buffer allocation failures, resulting in the device to not pass traffic anymore until it is manually recovered with a restart.This issue affects Junos OS:

24.4 releases before 24.4R2,
25.2 releases before 25.2R1-S1, 25.2R2.

This issue does not affect Junos OS releases before 24.4R1.

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

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{
  "affected": [],
  "aliases": [
    "CVE-2026-33781"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-754"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-04-09T22:16:27Z",
    "severity": "HIGH"
  },
  "details": "An Improper Check for Unusual or Exceptional Conditions vulnerability in the packet forwarding engine (pfe) of Juniper Networks Junos OS on specific EX and QFX Series devices allow an unauthenticated, adjacent attacker to cause a complete Denial of Service (DoS).\n\nOn EX4k, and QFX5k platforms configured as service-provider edge devices, if L2PT is enabled on the UNI and VSTP is enabled on NNI in VXLAN scenarios, receiving VSTP BPDUs on UNI leads to packet buffer allocation failures, resulting in the device to not pass traffic anymore until it is manually recovered with a restart.This issue affects Junos OS:\n\n\n\n  *  24.4 releases before 24.4R2,\n  *  25.2 releases before 25.2R1-S1, 25.2R2.\n\n\n\n\nThis issue does not affect Junos OS releases before 24.4R1.",
  "id": "GHSA-gv4f-m3jw-j3h9",
  "modified": "2026-04-10T00:30:29Z",
  "published": "2026-04-10T00:30:29Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-33781"
    },
    {
      "type": "WEB",
      "url": "https://kb.juniper.net/JSA107869"
    }
  ],
  "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-2026-33781 (GCVE-0-2026-33781)

Vulnerability from cvelistv5 – Published: 2026-04-09 21:35 – Updated: 2026-04-10 14:10

Title

Junos OS: EX Series, QFX Series: In a VXLAN scenario when specific control protocol packets are received, memory leaks and eventually no traffic is passed

Summary

An Improper Check for Unusual or Exceptional Conditions vulnerability in the packet forwarding engine (pfe) of Juniper Networks Junos OS on specific EX and QFX Series devices allow an unauthenticated, adjacent attacker to cause a complete Denial of Service (DoS). On EX4k, and QFX5k platforms configured as service-provider edge devices, if L2PT is enabled on the UNI and VSTP is enabled on NNI in VXLAN scenarios, receiving VSTP BPDUs on UNI leads to packet buffer allocation failures, resulting in the device to not pass traffic anymore until it is manually recovered with a restart.This issue affects Junos OS: * 24.4 releases before 24.4R2, * 25.2 releases before 25.2R1-S1, 25.2R2. This issue does not affect Junos OS releases before 24.4R1.

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-754 - Improper Check for Unusual or Exceptional Conditions

Assigner

juniper

References

URL

Tags

https://kb.juniper.net/JSA107869

vendor-advisory

Impacted products

	Vendor	Product	Version
	Juniper Networks	Junos OS	Affected: 24.4 , < 24.4R2 (semver) Affected: 25.2 , < 25.2R1-S1, 25.2R2 (semver) Unaffected: 0 , < 24.4R1 (semver)

Date Public ?

2026-04-08 16:00

Show details on NVD website

JSON

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                "role": "CISA Coordinator",
                "timestamp": "2026-04-10T14:09:58.383485Z",
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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-GV4F-M3JW-J3H9

CVE-2026-33781 (GCVE-0-2026-33781)

Tags

Sightings

Nomenclature