7.5
HIGH CVSS 3.1
CVE-2026-7776
Boundary Workers Vulnerable to Denial of Service During TLS Handshake
Description

Boundary Community Edition and Boundary Enterprise (“Boundary”) workers are vulnerable to a denial-of-service condition during node enrollment TLS handshakes. An attacker with network access to the worker authentication listener may open a connection and delay or withhold the client certificate during the TLS handshake, causing worker connection handling to block. This may prevent legitimate worker connections from being accepted or routed. This vulnerability, CVE-2026-7776, is fixed in Boundary 0.21.3, 0.20.3, 0.19.5.

INFO

Published Date :

May 4, 2026, 10:16 p.m.

Last Modified :

May 4, 2026, 10:16 p.m.

Remotely Exploit :

No
Affected Products

The following products are affected by CVE-2026-7776 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH 67fedba0-ff2e-4543-ba5b-aa93e87718cc
CVSS 3.1 HIGH [email protected]
Solution
Update Boundary to a fixed version to resolve the denial-of-service condition.
  • Upgrade Boundary to version 0.21.3 or later.
  • Apply version 0.20.3 or 0.19.5 if upgrading is not possible.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-7776.

URL Resource
https://discuss.hashicorp.com/t/hcsec-2026-11-boundary-workers-vulnerable-to-denial-of-service-during-tls-handshake
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-7776 is associated with the following CWEs:

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-7776 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-7776 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    May. 04, 2026

    Action Type Old Value New Value
    Added Description Boundary Community Edition and Boundary Enterprise (“Boundary”) workers are vulnerable to a denial-of-service condition during node enrollment TLS handshakes. An attacker with network access to the worker authentication listener may open a connection and delay or withhold the client certificate during the TLS handshake, causing worker connection handling to block. This may prevent legitimate worker connections from being accepted or routed. This vulnerability, CVE-2026-7776, is fixed in Boundary 0.21.3, 0.20.3, 0.19.5.
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
    Added CWE CWE-770
    Added Reference https://discuss.hashicorp.com/t/hcsec-2026-11-boundary-workers-vulnerable-to-denial-of-service-during-tls-handshake
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.