CVE-2026-33773
Published: April 9, 2026· Updated: Apr 13, 2026
Official Description
An Incorrect Initialization of Resource vulnerability in the packet forwarding engine (pfe) of Juniper Networks Junos OS on specific EX Series and QFX Series device allows an unauthenticated, network-based attacker to cause an integrity impact to downstream networks.
When the same family inet or inet6 filter is applied on an IRB interface and on a physical interface as egress filter on EX4100, EX4400, EX4650 and QFX5120 devices, only one of the two filters will be applied, which can lead to traffic being sent out one of these interfaces which should have been blocked.
This issue affects Junos OS on EX Series and QFX Series:
* 23.4 version 23.4R2-S6,
* 24.2 version 24.2R2-S3.
No other Junos OS versions are affected.
Technical Analysis
CVE-2026-33773 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.
The vulnerability has a "Changed" scope, meaning successful exploitation can impact components beyond the vulnerable component itself — such as the host operating system or adjacent services.
CVSS v3.1 Vector Breakdown
Affected Vendors & Products
Exploit & PoC Resources
All References (1)
Quick Facts
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2026-33773 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts