VU#212479: Sentry Seer vulnerability allows attacker-controlled input to be executed in a privileged environment

Overview A vulnerability exists in Sentry Seer when the system is configured to automatically hand issues to a coding agent for remediation. Successful exploitation results in arbitrary code execution within the coding‑agent environment and access to connected source repositories. This vulnerability is tracked as CVE-2026-90999. Description Sentry is a software error‑monitoring and performance‑tracking platform used by developers to detect, diagnose, and understand issues in their applications. It collects telemetry such as exceptions, stack traces, logs, and performance data from applications. Built into Sentry, Seer acts as an automated debugging assistant that converts telemetry into actionable remediation steps and can hand off issues to an integrated coding agent to propose code fixes. Because Sentry front-end projects commonly expose a public DSN (Data Source Name) to allow browsers to submit this telemetry, an attacker can craft and submit malicious events through this public endpoint. When Seer is enabled to automatically pass issues to a coding agent, these attacker-supplied events can traverse multiple trust boundaries. Ultimately, malicious event fields propagate thro...