IntelliJ IDEA CVE-2026-86503

The victim must open a malicious project file in IntelliJ IDEA before version 2026.2.2 that contains a crafted Kubernetes spec-source URL directive pointing to an attacker-controlled or internal-network target. The Kubernetes integration feature must be active (present by default in IntelliJ IDEA Ultimate; may require plugin in Community). User interaction is required - the developer must affirmatively open the project. The SSRF request originates from the developer's machine, so exploitation is limited to hosts reachable from that machine's network context. No authentication to the IDE or the target host is required. Exploitation does NOT occur over a network connection to IntelliJ IDEA itself; the attacker's leverage is entirely through the crafted project artifact.

The CVSS 3.1 score of 3.3 (Low) reflects the realistic attack profile well: AV:L requires the victim to open a locally-present project file, UI:R confirms required user interaction, and C:L caps the impact at partial information disclosure. No EPSS data was supplied; given the niche exploitation scenario targeting developers and the absence of KEV listing or public POC, real-world risk is low in the near term. The principal concern is supply-chain targeting: an attacker could publish a malicious open-source project or send a crafted repository to developers working with Kubernetes-based infrastructure. Developers who routinely clone and open unreviewed repositories (e.g., security researchers, open-source contributors) are the realistic at-risk population. The SSRF could reach cloud metadata services (AWS IMDSv1, GCP metadata endpoint) if the developer's machine has access, elevating the practical impact beyond C:L in those environments - a factor not captured in the base score.

An attacker publishes a Kubernetes-based open-source project on GitHub containing a malicious spec-source URL pointing to an internal cloud metadata endpoint (e.g., http://169.254.169.254/latest/meta-data/). A developer clones and opens the project in IntelliJ IDEA; the IDE silently fetches the URL during project initialization, returning instance metadata or internal service responses to the attacker-controlled server. No public POC has been identified, but the technique mirrors well-understood IDE supply-chain attacks.