SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityDeferred

CVE-2026-82439

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…

CRITICAL 9.8EPSS 0.52%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.52%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

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.

CVSS 3.1
9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
0.52% probability · 43th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-770
Source
security@apache.org
EPSS trend
0%3%5%19 September 2026: 0.52%19 September 202619 September 2026

EPSS 0.5% since 19 September 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.