CVE-2026-33781

  1. OpenCVE
  2. Vulnerabilities (CVE)
  3. CVE-2026-33781
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.

6.5 /10

CVSS v3 : MEDIUM

V3 Legend

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector ADJACENT_NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References
Link Resource
https://kb.juniper.net/JSA107869 Mitigation Vendor Advisory
Configurations

Configuration 1 (hide)

AND
OR cpe:2.3:o:juniper:junos:24.4:-:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:24.4:r1:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:24.4:r1-s2:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:24.4:r1-s3:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:25.2:-:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:25.2:r1:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:25.2:r2:*:*:*:*:*:*
OR cpe:2.3:h:juniper:ex4000:-:*:*:*:*:*:*:*
cpe:2.3:h:juniper:ex4100:-:*:*:*:*:*:*:*
cpe:2.3:h:juniper:ex4100-f:-:*:*:*:*:*:*:*
cpe:2.3:h:juniper:ex4100-h:-:*:*:*:*:*:*:*
cpe:2.3:h:juniper:ex4300:-:*:*:*:*:*:*:*
cpe:2.3:h:juniper:ex4400:-:*:*:*:*:*:*:*
cpe:2.3:h:juniper:ex4600:-:*:*:*:*:*:*:*
cpe:2.3:h:juniper:ex4650:-:*:*:*:*:*:*:*
cpe:2.3:h:juniper:qfx5110:-:*:*:*:*:*:*:*
cpe:2.3:h:juniper:qfx5120:-:*:*:*:*:*:*:*
cpe:2.3:h:juniper:qfx5130:-:*:*:*:*:*:*:*
cpe:2.3:h:juniper:qfx5200:-:*:*:*:*:*:*:*
cpe:2.3:h:juniper:qfx5210:-:*:*:*:*:*:*:*
cpe:2.3:h:juniper:qfx5220:-:*:*:*:*:*:*:*
cpe:2.3:h:juniper:qfx5230-64cd:-:*:*:*:*:*:*:*
cpe:2.3:h:juniper:qfx5240:-:*:*:*:*:*:*:*
cpe:2.3:h:juniper:qfx5241:-:*:*:*:*:*:*:*
cpe:2.3:h:juniper:qfx5700:-:*:*:*:*:*:*:*
History

No history.

Information

Published : 2026-04-09 22:16

Updated : 2026-06-17 10:38

NVD link : CVE-2026-33781

Mitre link : CVE-2026-33781

CVE.ORG link : CVE-2026-33781

JSON object : View

Products Affected

juniper

  • ex4600
  • qfx5700
  • ex4300
  • ex4650
  • ex4100-h
  • ex4100-f
  • qfx5240
  • qfx5200
  • qfx5220
  • qfx5130
  • ex4100
  • qfx5120
  • qfx5210
  • ex4400
  • ex4000
  • qfx5230-64cd
  • qfx5110
  • qfx5241
  • junos
CWE
CWE-754

Improper Check for Unusual or Exceptional Conditions