Division by zero Affecting halfgaar/FlashMQ package, versions [,1.26.1)
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-UNMANAGED-HALFGAARFLASHMQ-16599134
- published9 May 2026
- disclosed8 May 2026
- creditRuoyyy
Introduced: 8 May 2026
CVE-2026-42209 (opens in a new tab)How to fix?
Upgrade halfgaar/FlashMQ to version 1.26.1 or higher.
Overview
Affected versions of this package are vulnerable to Division by zero in the set_retained_message_defer_timeout and set_retained_message_defer_timeout_spread process when both are configured to non-default values. An attacker can cause the broker to crash by sending a specially crafted retained publish request. This is only exploitable if both set_retained_message_defer_timeout and set_retained_message_defer_timeout_spread are set to non-default values.