CVE-2026-8763 - Vulnerability Details - OpenCVE

In Bouncy Castle for Java before 1.85, Name Constraints bypass via trailing dot in rfc822Name and URI. This issue also affects Bouncy Castle for Java LTS before 2.73.12, and Bouncy Castle for Java FIPS (BC-FJA) before bc-fips 1.0.2.7 (1.0.X series), 2.0.2 (2.0.X series) and 2.1.3 (2.1.X series).

Attack Vector Network

Attack Complexity Low

Privileges Required None

Attack Requirements None

User Interaction None

Vulnerable System Confidentiality Impact High

Vulnerable System Integrity Impact High

Vulnerable System Availability Impact None

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

No CVSS v3.1

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Key SSVC decision points have not yet been added.

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OpenCVE Enrichment is a feature of OpenCVE that uses AI to automatically link vendors and products to CVEs. Learn more on GitHub.

Vendors	Products

References

Link	Providers
https://github.com/bcgit/bc-java/commit/2c28b253a44681fbbc562561eab6ad383d2ae558
https://github.com/bcgit/bc-java/wiki/CVE%E2%80%902026%E2%80%908763

History

Mon, 03 Aug 2026 09:00:00 +0000

Type	Values Removed	Values Added
References	https://github.com/bcgit/bc-java/wiki/CVE-2026-8763	https://github.com/bcgit/bc-java/wiki/CVE%E2%80%902026%E2%80%908763

Mon, 03 Aug 2026 01:15:00 +0000

Type	Values Removed	Values Added
Description		In Bouncy Castle for Java before 1.85, Name Constraints bypass via trailing dot in rfc822Name and URI. This issue also affects Bouncy Castle for Java LTS before 2.73.12, and Bouncy Castle for Java FIPS (BC-FJA) before bc-fips 1.0.2.7 (1.0.X series), 2.0.2 (2.0.X series) and 2.1.3 (2.1.X series).
Title		Name Constraints bypass via trailing dot in rfc822Name and URI
Weaknesses		CWE-295
References		https://github.com/bcgit/bc-java/commit/2c28b253a44681fbbc562561eab6ad383d2ae558 https://github.com/bcgit/bc-java/wiki/CVE-2026-8763
Metrics		cvssV4_0 `{'score': 9.3, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/U:Amber'}`

MITRE

Status: PUBLISHED

Assigner: bcorg

Published: 2026-08-03T00:36:05.088Z

Updated: 2026-08-03T08:09:13.960Z

Reserved: 2026-05-17T06:03:57.082Z

Link: CVE-2026-8763

Vulnrichment

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NVD

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Redhat

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OpenCVE Enrichment

Updated: 2026-08-03T09:15:03Z

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