Uncontrolled Recursion Affecting @nestjs/microservices package, versions <11.1.19
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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- published16 Apr 2026
- disclosed14 Apr 2026
- credithwpark6804-gif
Introduced: 14 Apr 2026
CVE-2026-40879 (opens in a new tab)How to fix?
Upgrade @nestjs/microservices to version 11.1.19 or higher.
Overview
@nestjs/microservices is a Nest - modern, fast, powerful node.js web framework (@microservices)
Affected versions of this package are vulnerable to Uncontrolled Recursion through the handleData() function in packages/microservices/helpers/json-socket.ts. An attacker can crash the TCP microservice by sending a large burst of pipelined "<len>#<json>" frames in a single read, causing recursive frame processing to exhaust the call stack and terminate the connection. When the service processes untrusted TCP input, a crafted stream of many small valid frames can bring down the microservice and prevent it from responding to subsequent requests.