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.
References
| Link | Resource |
|---|---|
| https://kb.juniper.net/JSA107869 | Mitigation Vendor Advisory |
Configurations
Configuration 1 (hide)
| AND |
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History
17 Apr 2026, 17:53
| Type | Values Removed | Values Added |
|---|---|---|
| CPE | cpe:2.3:h:juniper:qfx5241:-:*:*:*:*:*:*:* cpe:2.3:h:juniper:ex4100-f:-:*:*:*:*:*:*:* cpe:2.3:h:juniper:qfx5240:-:*:*:*:*:*:*:* cpe:2.3:h:juniper:ex4400:-:*:*:*:*:*:*:* cpe:2.3:o:juniper:junos:24.4:r1:*:*:*:*:*:* cpe:2.3:o:juniper:junos:24.4:r1-s2:*:*:*:*:*:* cpe:2.3:h:juniper:ex4000:-:*:*:*:*:*:*:* cpe:2.3:h:juniper:qfx5220:-:*:*:*:*:*:*:* cpe:2.3:o:juniper:junos:25.2:-:*:*:*:*:*:* cpe:2.3:h:juniper:ex4100:-:*:*:*:*:*:*:* cpe:2.3:h:juniper:qfx5110:-:*:*:*:*:*:*:* cpe:2.3:h:juniper:qfx5700:-:*:*:*:*:*:*:* cpe:2.3:h:juniper:ex4300:-:*:*:*:*:*:*:* cpe:2.3:o:juniper:junos:25.2:r2:*:*:*:*:*:* cpe:2.3:h:juniper:qfx5120:-:*:*:*:*:*:*:* cpe:2.3:o:juniper:junos:24.4:r1-s3:*:*:*:*:*:* cpe:2.3:h:juniper:ex4600:-:*:*:*:*:*:*:* cpe:2.3:h:juniper:qfx5130:-:*:*:*:*:*:*:* cpe:2.3:h:juniper:qfx5210:-:*:*:*:*:*:*:* cpe:2.3:h:juniper:qfx5230-64cd:-:*:*:*:*:*:*:* cpe:2.3:o:juniper:junos:25.2:r1:*:*:*:*:*:* cpe:2.3:h:juniper:qfx5200:-:*:*:*:*:*:*:* cpe:2.3:h:juniper:ex4100-h:-:*:*:*:*:*:*:* cpe:2.3:h:juniper:ex4650:-:*:*:*:*:*:*:* cpe:2.3:o:juniper:junos:24.4:-:*:*:*:*:*:* |
|
| References | () https://kb.juniper.net/JSA107869 - Mitigation, Vendor Advisory | |
| First Time |
Juniper qfx5700
Juniper ex4100-h Juniper ex4650 Juniper qfx5120 Juniper Juniper qfx5210 Juniper ex4100 Juniper qfx5241 Juniper junos Juniper qfx5240 Juniper ex4100-f Juniper qfx5200 Juniper ex4000 Juniper qfx5230-64cd Juniper ex4300 Juniper qfx5220 Juniper ex4400 Juniper qfx5130 Juniper qfx5110 Juniper ex4600 |
09 Apr 2026, 22:16
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-04-09 22:16
Updated : 2026-04-17 17:53
NVD link : CVE-2026-33781
Mitre link : CVE-2026-33781
CVE.ORG link : CVE-2026-33781
JSON object : View
Products Affected
juniper
- qfx5130
- ex4300
- ex4400
- ex4650
- qfx5230-64cd
- ex4600
- qfx5200
- junos
- ex4100
- qfx5241
- qfx5240
- qfx5120
- qfx5110
- qfx5220
- ex4100-f
- ex4000
- qfx5700
- qfx5210
- ex4100-h
CWE
CWE-754
Improper Check for Unusual or Exceptional Conditions