How severe is CVE-2026-33803?

CVE-2026-33803 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability low.

Is CVE-2026-33803 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (18th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-33803?

CVE-2026-33803 primarily affects Juniper Junos Os Evolved. In total, 48 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-33803?

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

When was CVE-2026-33803 published?

CVE-2026-33803 was published on 2026-07-09 and last updated on 2026-07-13.

CVE-2026-33803

CVE-2026-33803 is a medium-severity vulnerability in Juniper Junos Os Evolved with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-923.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v4: 6.9
EPSS exploit prediction: 0% (18th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-923
Affected product: Juniper Junos Os Evolved
Published: 2026-07-09
Last modified: 2026-07-13

Description

An Improper Restriction of Communication Channel to Intended Endpoints vulnerability in Juniper Networks Junos OS Evolved allows an unauthenticated, network-based attacker to cause a limited information disclosure and availability impact to the device. Due to a wrong initialization, a process which should only be able to communicate internally within the device can be reached over the network via an open port. This leads to a device being inadvertently exposed and increased CPU cycles spent processing ingress packets. This issue affects Junos OS Evolved: * all versions before 23.2R2-S7-EVO, * 23.4 versions before 23.4R2-S8-EVO, * 24.2 versions before 24.2R2-S5-EVO, * 24.4 versions before 24.4R2-S4-EVO, * 25.2 versions before 25.2R2-S1-EVO, * 25.4 versions before 25.4R1-S2-EVO.

Frequently asked questions

What is CVE-2026-33803?: An Improper Restriction of Communication Channel to Intended Endpoints vulnerability in Juniper Networks Junos OS Evolved allows an unauthenticated, network-based attacker to cause a limited information disclosure and availability impact to the device. Due to a wrong initialization, a process which should only be able to communicate internally within the device can be reached over the network via an open port. This leads to a device being inadvertently exposed and increased CPU cycles spent processing ingress packets. This issue affects Junos OS Evolved: * all versions before 23.2R2-S7-EVO, * 23.4 versions before 23.4R2-S8-EVO, * 24.2 versions before 24.2R2-S5-EVO, * 24.4 versions before 24.4R2-S4-EVO, * 25.2 versions before 25.2R2-S1-EVO, * 25.4 versions before 25.4R1-S2-EVO.
How severe is CVE-2026-33803?: CVE-2026-33803 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability low.
Is CVE-2026-33803 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (18th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-33803?: CVE-2026-33803 primarily affects Juniper Junos Os Evolved. In total, 48 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-33803?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2026-33803 published?: CVE-2026-33803 was published on 2026-07-09 and last updated on 2026-07-13.

References

https://supportportal.juniper.net/JSA110078

Affected products (48)

cpe:2.3:o:juniper:junos_os_evolved:*:*:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:23.2:-:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:23.2:r1:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:23.2:r1-s1:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:23.2:r1-s2:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:23.2:r2:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:23.2:r2-s1:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:23.2:r2-s2:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:23.2:r2-s3:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:23.2:r2-s4:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:23.2:r2-s5:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:23.2:r2-s6:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:23.4:-:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:23.4:r1:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:23.4:r1-s1:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:23.4:r1-s2:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:23.4:r2:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:23.4:r2-s1:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:23.4:r2-s2:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:23.4:r2-s3:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:23.4:r2-s4:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:23.4:r2-s5:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:23.4:r2-s6:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:23.4:r2-s7:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:24.2:-:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:24.2:r1:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:24.2:r1-s2:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:24.2:r2:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:24.2:r2-s1:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:24.2:r2-s2:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:24.2:r2-s3:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:24.2:r2-s4:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:24.4:-:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:24.4:r1:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:24.4:r1-s2:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:24.4:r1-s3:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:24.4:r2:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:24.4:r2-s1:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:24.4:r2-s2:*:*:*:*:*:*
cpe:2.3:o:juniper:junos_os_evolved:24.4:r2-s3:*:*:*:*:*:*

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