Routinator CVE-2026-49235

Exploitation requires the target Routinator instance to fetch RRDP repository content (notification.xml, snapshot, or delta) from a publication point controlled by the attacker - this is the default fetch mechanism for most RPKI trust anchors, so no special Routinator configuration is needed beyond having RRDP enabled (the default). No authentication, user interaction, or local access is required. The limiting factor is delivery: the attacker must either operate a publication point that appears in Routinator's trust anchor chain or compromise an existing publication point, rather than being able to crash arbitrary internet-exposed Routinator hosts directly. Versions prior to 0.15.2 are vulnerable across all platforms NLnet Labs ships Routinator for.

The CVSS 4.0 vector (AV:N/AC:L/AT:N/PR:N/UI:N) indicates a network-reachable, low-complexity, unauthenticated trigger with subsequent system availability impact (SA:L) in addition to vulnerable-system availability (VA:H), justifying the 8.7 base score. However, real-world exploitability is conditioned on Routinator fetching RRDP content from a malicious or compromised publication point - typically reached through the trust anchor chain - rather than an attacker sending a packet directly to the host, so the AV:N rating is technically accurate but contextually narrower than an internet-facing service vulnerability. EPSS and KEV status are not provided; no public exploit identified at time of analysis and there is no indication of active exploitation. The practical priority is high for ISPs, IXPs, and operators using Routinator in production RPKI pipelines because a crash blocks VRP refresh and can cause stale validation state, but the attacker must control a reachable RRDP repository to deliver the payload.

An attacker who controls or compromises an RRDP publication point reachable through a configured trust anchor (or who can man-in-the-middle an RRDP fetch where TLS validation is weak) serves a snapshot or delta XML document containing a crafted Document Type Definition. When Routinator retrieves and parses the document during its scheduled update cycle, the malformed DTD triggers an unhandled error and the process crashes, stalling VRP generation for downstream routers. No public exploit identified at time of analysis.