Legion of the Bouncy Castle Bouncy Castle for Java up to 2.1.2 Name Constraints input validation

Summaryinfo

A vulnerability, which was classified as critical, has been found in Legion of the Bouncy Castle Bouncy Castle for Java, Bouncy Castle for Java LTS and Bouncy Castle for Java FIPS up to 1.84/2.73.11/bc-fips 1.0.2.6/2.0.1/2.1.2. The affected element is an unknown function of the component Name Constraints. This manipulation causes input validation. This vulnerability is registered as CVE-2026-8763. Remote exploitation of the attack is possible. No exploit is available.

Detailsinfo

A vulnerability classified as critical was found in Legion of the Bouncy Castle Bouncy Castle for Java, Bouncy Castle for Java LTS and Bouncy Castle for Java FIPS up to 1.84/2.73.11/bc-fips 1.0.2.6/2.0.1/2.1.2. Affected by this vulnerability is an unknown functionality of the component Name Constraints. The manipulation with an unknown input leads to a input validation vulnerability. The CWE definition for the vulnerability is CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

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).

It is possible to read the advisory at github.com. This vulnerability is known as CVE-2026-8763 since 05/17/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. The technical details are unknown and an exploit is not publicly available.

Upgrading to version 1.85, 2.73.12, bc-fips 1.0.2.7, 2.0.2 or 2.1.3 eliminates this vulnerability.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

• Programming Language Software

Vendor

• Legion of the Bouncy Castle

Name

• Bouncy Castle for Java
• Bouncy Castle for Java FIPS
• Bouncy Castle for Java LTS

Version

• 1.0
• 1.1
• 1.2
• 1.3
• 1.4
• 1.5
• 1.6
• 1.7
• 1.8
• 1.9
• 1.10
• 1.11
• 1.12
• 1.13
• 1.14
• 1.15
• 1.16
• 1.17
• 1.18
• 1.19
• 1.20
• 1.21
• 1.22
• 1.23
• 1.24
• 1.25
• 1.26
• 1.27
• 1.28
• 1.29
• 1.30
• 1.31
• 1.32
• 1.33
• 1.34
• 1.35
• 1.36
• 1.37
• 1.38
• 1.39
• 1.40
• 1.41
• 1.42
• 1.43
• 1.44
• 1.45
• 1.46
• 1.47
• 1.48
• 1.49
• 1.50
• 1.51
• 1.52
• 1.53
• 1.54
• 1.55
• 1.56
• 1.57
• 1.58
• 1.59
• 1.60
• 1.61
• 1.62
• 1.63
• 1.64
• 1.65
• 1.66
• 1.67
• 1.68
• 1.69
• 1.70
• 1.71
• 1.72
• 1.73
• 1.74
• 1.75
• 1.76
• 1.77
• 1.78
• 1.79
• 1.80
• 1.81
• 1.82
• 1.83
• 1.84
• 2.0.0
• 2.0.1
• 2.1.0
• 2.1.1
• 2.1.2
• 2.73.0
• 2.73.1
• 2.73.2
• 2.73.3
• 2.73.4
• 2.73.5
• 2.73.6
• 2.73.7
• 2.73.8
• 2.73.9
• 2.73.10
• 2.73.11
• bc-fips 1.0.2.0
• bc-fips 1.0.2.1
• bc-fips 1.0.2.2
• bc-fips 1.0.2.3
• bc-fips 1.0.2.4
• bc-fips 1.0.2.5
• bc-fips 1.0.2.6

CPE 2.3info

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CPE 2.2info

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Entryinfo

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