# CVE-2026-75806: OpenSSL DTLS denial of service in AEAD record validation

Source: https://junglewise.ai/threats/cve-2026-75806-issue-summary-an-established-dtls-1-2-association-using-an-aead  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-29. Updated: 2026-09-29  
License: CC BY 4.0 with a link back

CVE-2026-75806 · Severity: medium · CVSS 5.3 · Published 2026-09-29

OpenSSL's DTLS 1.2 implementation does not properly validate record length before processing AEAD-encrypted data. An attacker on the network can send a specially crafted short datagram to tear down an existing DTLS connection without authentication, causing a denial of service to that specific session. This affects applications using OpenSSL for DTLS-based communication such as VoIP, real-time games, or secure IoT protocols.

Technologies: [OpenSSL](https://junglewise.ai/threats/technologies/openssl). Vendors: [OpenSSL](https://junglewise.ai/threats/vendors/openssl).

## Quick answers

**Is CVE-2026-75806 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-75806 being exploited in the wild.

**How severe is CVE-2026-75806?** Medium severity, with a CVSS score of 5.3, published 29 September 2026.

**Which products and versions are affected?** OpenSSL 1.1.1 and 3.0.

**Is there a fix for CVE-2026-75806?** 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-2026-75806 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-75806?** Check whether you run OpenSSL 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

The vulnerability is in the record layer validation for DTLS 1.2 connections protected by AEAD cipher suites. When a record shorter than the mandatory explicit IV and authentication tag overhead is received, the cipher implementation rejects the length but the record layer incorrectly treats this as an internal failure instead of a failed authentication check. An unauthenticated attacker with network access to the DTLS association can inject a malformed datagram to trigger connection termination without knowing any session keys.

## Affected products

- OpenSSL OpenSSL 1.1.1 and 3.0

## Timeline

- 2026-09-29: disclosed

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