Apache APISIX EUVD-2026-90767

Requires a route that has the batch-requests plugin enabled AND the batch endpoint publicly exposed to unauthenticated callers (per CVSS AT:P / 'batch endpoint is publicly exposed'). Against such a route, no authentication, user interaction, or local access is needed (PR:N/UI:N/AV:N). Limiting factors: deployments that do not use the batch-requests plugin, or that restrict/do not expose the batch endpoint, are not exploitable; impact is confined to availability (worker OOM) with no confidentiality or integrity effect. Affected versions are Apache APISIX 1.3.0 through 3.18.0; upgrading to 3.19.0 remediates.

This is a credible operational-availability risk, not an inflated high-CVSS artifact. The CVSS 4.0 vector (AV:N/AC:L/AT:P/PR:N/UI:N) describes a network-reachable, low-complexity, unauthenticated flaw whose only impact is availability (VA:H; VC:N/VI:N), consistent with CWE-770 (allocation of resources without limits) causing an OOM condition in a gateway worker. The AT:P (attack-requirement: Present) element is important - exploitation is NOT universal: it depends on a route actually using the batch-requests plugin AND the batch endpoint being publicly exposed, so default/hardened deployments are not affected. There is no EPSS score, no CISA KEV listing, and no public POC referenced in the provided data, so exploitation status is 'no public exploit identified at time of analysis' - this is a patch-and-move-on availability bug rather than an actively-weaponized threat. The dominant risk driver is that APISIX is an edge API gateway: a successful OOM on the worker degrades or drops traffic for everything behind the gateway, amplifying the blast radius of an otherwise availability-only issue. No conflicting signals were found; the single Apache advisory reference, affected range (1.3.0 through 3.18.0), and fixed version (3.19.0) are internally consistent.

An attacker identifies an APISIX route that enables the batch-requests plugin with its batch endpoint publicly reachable, then sends a crafted batch request (e.g., an oversized or deeply-nested batch payload) that the plugin expands without limit. The unbounded allocation exhausts memory and drives the OpenResty/nginx worker into an out-of-memory state, disrupting gateway traffic. No authentication is required and attack complexity is low; no public POC is referenced in the available data.