Junos OS CVE-2026-102014

The Junos OS device must be configured to use RADIUS for authentication (invoking the authd process), AND the attacker must be able to influence RADIUS server responses - either by compromising the configured RADIUS server or by occupying an adjacent-network position allowing injection or modification of RADIUS responses (consistent with AV:A). Exploitation is LIMITED by these factors: RADIUS authentication must be enabled (not applicable to devices using local or other auth backends), the attacker needs control over the authentication-network trust path, and only adjacent (not arbitrary remote internet) reachability is sufficient. No end-user interaction on an attacker-controlled page is required, but an authentication exchange with the malicious RADIUS server must occur.

CVSS 4.0 rates this 8.7 (High) driven by AV:A/AC:L/PR:N/UI:N with High confidentiality, integrity and availability impact, reflecting unauthenticated root-level code execution. However, the single strongest mitigating signal is the attack vector: AV:A (Adjacent) plus the prerequisite that the attacker must already be able to influence a configured RADIUS server means this is NOT a straightforward internet-facing remote exploit - it requires either a compromised/malicious RADIUS server or a privileged position on the authentication network path. No EPSS score, CISA KEV listing, or public POC was provided in the input, so there is no public exploit identified at time of analysis and no evidence of active exploitation. The supplemental metrics reinforce a targeted profile: AU:Y (automatable) and V:C (concentrated value) suggest high value if the precondition is met, but the dependency on controlling RADIUS responses makes widespread opportunistic exploitation unlikely. Net assessment: a genuine high-severity issue warranting prompt patching for organizations that use RADIUS authentication on Junos devices, but the RADIUS-influence precondition substantially narrows the realistic attacker population versus a raw AV:N network flaw.

An attacker who controls or can impersonate the RADIUS server configured for Junos authentication (via a compromised RADIUS host or an adjacent-network man-in-the-middle position) crafts a malicious RADIUS response. When a user or administrator authenticates, the authd process parses the response and triggers a stack-based buffer overflow, crashing authd (denial of service) or executing arbitrary code with root privileges. No public proof-of-concept was identified in the provided data.