Quick answers
- Is CVE-2026-83869 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-83869 being exploited in the wild.
- How severe is CVE-2026-83869?
- Critical severity, with a CVSS score of 9.8, published 13 October 2026.
- Which products and versions are affected?
- DNS Server.
- Is there a fix for CVE-2026-83869?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-83869 attacked?
- It is attacked over the network, in a hosted service.
- Am I affected by CVE-2026-83869?
- Check whether you run Microsoft Windows 10 1607, Microsoft Windows 10 1809, Microsoft Windows 10 21h2 or one of the others listed. 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 (wraparound) vulnerability exists in DNS Server's packet handling code, allowing an attacker to send a specially crafted DNS request that triggers memory corruption. The vulnerability requires no authentication and can be exploited remotely via the network, enabling remote code execution with the privileges of the DNS service.
Affected products
- DNS Server
Timeline
- 2026-10-13: disclosed