Vulnerabilities

Vulnerability · CVE-2026-33773

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 al…

Published Apr 9, 2026 · catalog updated Jun 17, 2026 · the affected product

Check if you run it

No confirmed exploitation is on record for CVE-2026-33773. EPSS is 0.31%. Act only if a listed version of the affected product is installed.

Gaps on this record

  • No plain product name is stored. The page cannot tell you which product to check.
  • No vendor fix or required action is stored. Compare the linked advisory before you change production.
Severity
Medium6.9
Known exploitation
Not in CISA/VulnCheck KEV
EPSS
0.31%
Remediation
Not established
Affected products
cpe juniper/junos

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.

Are you affected?

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The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.

  • cpe juniper/junos23.4
  • cpe juniper/junos24.2

How to fix CVE-2026-33773

What to do

Three questions, each answered from this record only. Confirm the vendor advisory before you patch.

Should you patch?

No confirmed exploitation is on record for CVE-2026-33773. EPSS is 0.31%. Act only if a listed version of the affected product is installed.

Which versions are affected?

Compare what you have installed with 23.4, 24.2. Compare the installed version with the linked vendor advisory before you change production.

What should an analyst verify?

No weakness class is stored. EPSS 0.31%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.

Code

The project this record applies to. Exploit listings stay in References.

No public source repository is identified for this product.

Timeline

Detection, updates, and resolution for this record.

  1. Apr 9, 2026 · NIST NVD

    Detected

    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, EX4

  2. Jun 17, 2026 · NIST NVD

    Updated

    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, EX4

Sources

  • CVE.orgVulnerability recordCVE-2026-33773

    Official CVE identifier

    cve.org
  • FIRST EPSSExploitation probabilityCVE-2026-33773

    30-day exploitation probability 0.3%

    first.org
  • NIST NVDVulnerability recordCVE-2026-33773

    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 sa

    nvd.nist.gov

References

Freshness

Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.