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 ?
CWE
- CWE-754 - Improper Check for Unusual or Exceptional Conditions
Assigner
References
| URL | Tags | ||||
|---|---|---|---|---|---|
|
|||||
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
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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.
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