Quick answers
- Is CVE-2026-42542 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-42542 being exploited in the wild.
- How severe is CVE-2026-42542?
- High severity, with a CVSS score of 7.5, published 10 June 2026.
- Which products and versions are affected?
- TAOS Data TDengine 3.4.0.0 - 3.4.1.5.
- Is there a fix for CVE-2026-42542?
- A patch was published on 2026-04-30: Version 3.4.1.6 released Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-42542 attacked?
- It is attacked over the network, in an operating system.
- Am I affected by CVE-2026-42542?
- Check whether you run TAOS Data TDengine at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
An integer underflow vulnerability exists in the `uvConnMayGetUserInfo()` function within `source/libs/transport/src/transSvr.c`. The root cause is a mixed-type subtraction involving the client-supplied `len` field and internal offsets without proper bounds checking. When an attacker sends a crafted RPC packet where `len` is smaller than the expected overhead, the subtraction results in a massive value (integer wrap-around), causing `memcpy` to trigger a segmentation fault. This can be exploited remotely without authentication or prior session state. The issue is resolved in version 3.4.1.6 by adding explicit length validation.
Affected products
- taosdata TDengine 3.4.0.0 - 3.4.1.5
Timeline
- 2026-04-30: patched: Version 3.4.1.6 released
- 2026-06-04: advisory: GitHub Security Advisory published
- 2026-06-10: disclosed: CVE published to NVD