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

Vulnerability from cvelistv5 – Published: 2026-04-09 21:35 – Updated: 2026-04-10 14:10
VLAI
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
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-10 14:09 UTC
CWE
  • CWE-754 - Improper Check for Unusual or Exceptional Conditions
Assigner
juniper CNA under the mitre root
CNA scorecard B 84/100 over 193 records in the last 180 days details
References
URL Tags
https://kb.juniper.net/JSA107869 vendor-advisory
Impacted products
Vendor Product Version CPE status
Juniper Networks Junos OS Affected: 24.4 , < 24.4R2 (semver)
Affected: 25.2 , < 25.2R1-S1, 25.2R2 (semver)
Unaffected: 0 , < 24.4R1 (semver)
guessed Create a notification for this product.
Date Public
2026-04-08 16:00
Show details on NVD website
To clipboard 

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}



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