Vulnerability in Bouncycastle Bc-Java
CVE-2026-13506
In Bouncy Castle for Java before 1.85, Lazy ASN.1 sequence forcing resets nesting-depth guard. 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).
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.005 (42.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 42nd percentile — 42.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.005 · change: +0.001
Affected products
- Bouncycastle Bc-Java
- Bouncycastle Bouncy Castle For Java Lts
- Bouncycastle Fips Java API
- Legion Of The Bouncy Castle Inc. Bc-Fja — versions 1.0.0, 2.0.0, 2.1.0
- Legion Of The Bouncy Castle Inc. Bc-Java — versions 0
- Legion Of The Bouncy Castle Inc. Bc-Lts-Java — versions 2.73.0
Weakness classification (CWE)
References
- 91579145-5d7b-4cc5-b925-a0262ff19630 (vendor-advisory, Third Party Advisory)
- 91579145-5d7b-4cc5-b925-a0262ff19630 (Patch, patch)
Frequently asked questions
- What is CVE-2026-13506?
- CVE-2026-13506 is a high-severity vulnerability in Bouncycastle Bc-Java, classified under Uncontrolled Recursion. CVSS score: 7.5/10. Published 2026-08-03.
- How severe is CVE-2026-13506?
- High severity. CVSS v3 base score is 7.5 out of 10.