CVE-2026-82439: Apache Storm DRPC: Unauthenticated Unbounded Memory Growth in DRPC

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-09-14 · updated 2026-09-14
Weakness: CWE-770

Description

Description The DRPC server kept a map from function name to request queue and created an entry the first time a function name was seen. No code path ever removed an entry: request cleanup removed the request from its queue, and the shutdown path drained queues, but the queue object and its map entry remained for the life of the process. Function names come from the client and are not constrained to functions any topology has registered, so the number of retained entries is bounded only by the number of distinct names an attacker chooses to send, and each retained entry holds the name itself. `drpc.authorizer` is unset by default, so no credentials are required to reach the endpoint. The retained state is permanent rather than a transient load spike, so the effect accumulates until the DRPC server exhausts its heap. Mitigation Upgrade to 3.1.0, where a function's queue is removed once nothing is waiting in it. Users who cannot upgrade immediately should configure `drpc.authorizer` so that only trusted principals can reach the DRPC endpoints, and should ensure the DRPC ports are not reachable from untrusted networks. Credit The ASF -- found using Claude agents to study the security of open-source projects, validated and reported by Apache Storm.

Affected products

Apache Software Foundation Apache Storm DRPC: from 3.0.0 before 3.1.0 — fixed in 3.1.0

How to fix

Upgrade to a fixed version: Apache Software Foundation Apache Storm DRPC 3.1.0. Check the vendor advisory for mitigations.

References

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