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Juniper disclosed two vulnerabilities affecting Junos OS and Junos OS Evolved that allow local attackers to escalate their impact on network devices. One issue, tracked as CVE-2026-33788, allows an authenticated local attacker on Junos OS Evolved to gain access to Flexible PIC Concentrators (FPCs), potentially exposing critical forwarding-plane components to unauthorized access.
A second flaw, CVE-2026-33793, affects Junos OS and Junos OS Evolved and can let a local low-privileged user compromise the system when an unsigned Python op script configuration is present. The advisories indicate that exploitation requires local access and, in the second case, a specific insecure configuration, making the issues especially relevant for organizations that permit shell or operational access on network infrastructure and rely on custom scripting features.
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2 events from the most recent confirmed update back to the earliest known activity.
Juniper published a security bulletin for CVE-2026-33793, warning that when an unsigned Python op script configuration is present, a local low-privileged user can compromise the system in Junos OS and Junos OS Evolved.
Juniper published a security bulletin for CVE-2026-33788, stating that a local authenticated attacker can gain access to FPCs in Junos OS Evolved.
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Juniper disclosed two security vulnerabilities affecting **Junos OS** and **Junos OS Evolved**, including a flaw in **EX Series** and **QFX Series** switches where applying the same egress filter to both an IRB and a physical interface can cause one of the filters not to be enforced. The issue, tracked as **`CVE-2026-33773`**, could undermine intended network policy enforcement by leaving traffic insufficiently filtered on affected deployments. Juniper also published an advisory for **`CVE-2026-33793`**, warning that when an unsigned Python op script configuration is present, a local low-privileged user may be able to compromise the system. The vulnerability affects Junos platforms that permit that configuration state and creates a path for local privilege escalation or broader device compromise, prompting administrators to review exposed systems and apply vendor fixes or mitigations from Juniper's security bulletins.
Apr 9, 2026
Juniper disclosed two security vulnerabilities affecting **Junos OS** and **Junos OS Evolved**, including a local privilege-escalation flaw tracked as **`CVE-2026-21916`** that allows a low-privileged user to escalate privileges and log in as **`root`**. The issue creates a path for attackers who already have limited access to gain full administrative control over affected devices, increasing the risk of device takeover and unauthorized configuration changes. Juniper also published an advisory for **`CVE-2026-21919`**, a denial-of-service condition in **Junos OS** and **Junos OS Evolved** where a high frequency of connecting and disconnecting **NETCONF** sessions can cause management-plane unavailability. The flaw can disrupt administrative access and network operations by making device management unavailable, compounding the impact of the privilege-escalation issue for organizations running affected Juniper infrastructure.
Apr 9, 2026
Juniper Networks released security updates for multiple vulnerabilities in **Junos OS** and **Junos OS Evolved** that could allow denial of service, bypass of security restrictions, or unauthorized access caused by incorrect initialization. The affected products should be assessed across network infrastructure where Junos software is deployed. Notable issues include **CVE-2026-57026**, a network-reachable, unauthenticated denial-of-service vulnerability rated **CVSS 7.5**, and **CVE-2026-57028**, a network-reachable, unauthenticated access-control vulnerability rated **CVSS 7.3**. Organizations should test and deploy Juniper’s available fixes promptly, prioritizing internet-facing and otherwise untrusted-network-reachable devices.
Sep 27, 2026