CVE-2026-7776

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.

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CVSS v3.1 Score

7.5

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS — Exploit Prediction

0.0003

Probability of exploitation

0.09%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-770 CWE-770

References

Other References

https://discuss.hashicorp.com/t/hcsec-2026-11-boundary-workers-vulnerable-to-denial-of-service-during-tls-handshake

Frequently Asked Questions

What is CVE-2026-7776? +

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. It has a CVSS v3.1 base score of 7.5 (HIGH).

How severe is CVE-2026-7776? +

CVE-2026-7776 has a CVSS v3.1 score of 7.5 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0003, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-7776? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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