# CVE-2026-42542 — Tdengine

> As of 2026-06-11, CVE-2026-42542 is a HIGH-severity vulnerability in Tdengine, CVSS v3.1 7.5. Threadlinqs Intelligence links 1 tracked threat campaign to CVE-2026-42542, most recently “CVE-2026-42542: TDengine unauthenticated integer underflow lets a single RPC packet crash taosd”.

**Last updated:** 2026-06-11

## What is CVE-2026-42542?

TDengine is an open source, time-series database optimized for Internet of Things devices. In versions 3.4.0.0 through 3.4.1.5, an unauthenticated remote attacker can crash the taosd server process by sending a single crafted RPC packet. No credentials or prior session state are required. Version 3.4.1.6 fixes the issue.

The record classifies CVE-2026-42542 under weakness class [CWE-191](https://cwe.mitre.org/data/definitions/191.html). Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs no prior authentication, needs no user interaction, and has high impact on availability. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 112 days ago.

## Severity and exploitation probability

- **CVSS v3.1 base score:** 7.5 — HIGH (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog
- **Threadlinqs priority:** 5.8/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- **Published:** 2026-06-10, last modified 2026-06-11

## Is CVE-2026-42542 being exploited?

Weaponised exploit code for CVE-2026-42542 is publicly available. 1 public proof-of-concept repository is tracked for this identifier.

- [trickest/cve](https://github.com/trickest/cve/blob/main/2026/CVE-2026-42542.md) (trickest)

## Affected products and versions

- **taosdata**: TDengine

## How to fix CVE-2026-42542

Vendor advisory: [https://github.com/taosdata/TDengine/security/advisories/GHSA-vg95-j2hf-hvjx](https://github.com/taosdata/TDengine/security/advisories/GHSA-vg95-j2hf-hvjx). Apply the vendor fix referenced above to every affected product listed in this record, then confirm the running version against the vendor advisory.

## Threat activity tracking CVE-2026-42542

1 tracked threat in the Threadlinqs corpus references CVE-2026-42542, either in the campaign’s CVE list or as an indicator on the campaign record.

- [CVE-2026-42542: TDengine unauthenticated integer underflow lets a single RPC packet crash taosd](https://intel.threadlinqs.com/threat/TL-2026-2746) — HIGH · 2026-09-28

## Sources

Enriched from CVE.org, NVD, public proof-of-concept repositories. Last verified by Threadlinqs on 2026-09-29. This product uses the NVD API but is not endorsed or certified by the NVD.

**Vendor advisory and patch**

- [github.com](https://github.com/taosdata/TDengine/security/advisories/GHSA-vg95-j2hf-hvjx)

**Other references**

- [github.com](https://github.com/taosdata/TDengine/releases/tag/ver-3.4.1.6)

Canonical: https://intel.threadlinqs.com/cve/CVE-2026-42542
Full detection coverage and IOCs for threats exploiting CVE-2026-42542 via the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp