CVE-2026-33803
Junos OS Evolved: A port which has been inadvertently exposed can be reached by an attacker
CVE-2026-33803 is a medium vulnerability (CVSS 6.9) in Juniper Junos Os Evolved, published July 9, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.35%, the 29th percentile. No source names a fixed version.
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- None
- Availability
- Low
Exploit likelihood
What each source reports
CVE List Score used
Junos OS Evolved: A port which has been inadvertently exposed can be reached by an attacker
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.
- Record
CVE-2026-33803- CVSS 4.0
- 6.9 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N/AU:Y/R:U/RE:M - CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L - Weakness
- CWE-923
- Updated
- 2026-11-02
EUVDEUVD-2026-42704
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.
- Record
EUVD-2026-42704- CVSS 4.0
- 6.9 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N/AU:Y/R:U/RE:M - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-xc4g-8c26-vcmf
An Improper Restriction of Communication Channel to Intended Endpoints vulnerability in Juniper...
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.
- Record
GHSA-xc4g-8c26-vcmf- CVSS 4.0
- 6.9 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:Y/R:U/V:X/RE:M/U:X - CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L - Weakness
- CWE-923
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2026-33803- CVSS 4.0
- 6.9 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:Y/R:U/V:X/RE:M/U:X - CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L - Weakness
- CWE-923
- Updated
- 2026-11-02
Affected products
History
| When | Changed | Sources |
|---|---|---|
| 2026-11-02 | created | CVE List, EUVD, GitHub Advisories, NVD |