CVE-2026-8763

critical · 9.3

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).

9.3

CVSS

0.4%

EPSS (exploit prob.)

37th

EPSS percentile

2026-08-03

Published

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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Amber

Weaknesses

CWE-295

Affected products

Vendor	Product	Affected versions
bouncycastle	bc-java	< 1.85
bouncycastle	bouncy_castle_for_java_lts	<= 2.73.11
bouncycastle	fips_java_api	>= 1.0.0, < 1.0.2.7
bouncycastle	fips_java_api	>= 2.0.0, < 2.0.2
bouncycastle	fips_java_api	>= 2.1.0, < 2.1.3

Check a specific version with /api/v1/cve/match.

References

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

Query this programmatically:

curl https://evil-db.io/api/v1/cve/CVE-2026-8763