How severe is CVE-2026-33773?

CVE-2026-33773 has a CVSS 3.x base score of 5.8, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2026-33773 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (10th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-33773?

CVE-2026-33773 primarily affects Juniper Junos. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-33773?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-33773 have an EU (EUVD) identifier?

Yes. CVE-2026-33773 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-21085.

When was CVE-2026-33773 published?

CVE-2026-33773 was published on 2026-04-09 and last updated on 2026-06-17.

CVE-2026-33773

CVE-2026-33773 is a medium-severity vulnerability in Juniper Junos with a CVSS 3.x base score of 5.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Medium (CVSS 3.x base score 5.8)
CVSS v4: 6.9
EPSS exploit prediction: 0% (10th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-21085
Affected product: Juniper Junos
Published: 2026-04-09
Last modified: 2026-06-17

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.

Frequently asked questions

What is 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 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.
How severe is CVE-2026-33773?: CVE-2026-33773 has a CVSS 3.x base score of 5.8, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2026-33773 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (10th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-33773?: CVE-2026-33773 primarily affects Juniper Junos. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-33773?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-33773 have an EU (EUVD) identifier?: Yes. CVE-2026-33773 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-21085.
When was CVE-2026-33773 published?: CVE-2026-33773 was published on 2026-04-09 and last updated on 2026-06-17.

References

https://kb.juniper.net/JSA107815

Affected products (2)

cpe:2.3:o:juniper:junos:23.4:r2-s6:*:*:*:*:*:*
cpe:2.3:o:juniper:junos:24.2:r2-s3:*:*:*:*:*:*

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