CVE-2026-21720

HighCVSS 7.5/10Last modified Jul 15, 2026

Description

Every uncached /avatar/:hash request spawns a goroutine that refreshes the Gravatar image. If the refresh sits in the 10-slot worker queue longer than three seconds, the handler times out and stops listening for the result, so that goroutine blocks forever trying to send on an unbuffered channel. Sustained traffic with random hashes keeps tripping this timeout, so goroutine count grows linearly, eventually exhausting memory and causing Grafana to crash on some systems.

Metrics

CVSS 3.1 7.5/10CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Weakness enumeration

CWE-400 CWE-703 CWE-772

Affected software

No affected versions have been published.

Timeline

Published: Jan 27, 2026
Last modified: Jul 15, 2026
NVD status: Modified

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