Uncontrolled recursion in the ASN.1 parser (Asn1InputStream, Asn1StreamParser) in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows a remote unauthenticated attacker to cause a denial of service via a crafted ASN.1 encoding of deeply nested constructed elements (for example SEQUENCE inside SEQUENCE, in definite-length DER or indefinite-length BER form), because each nesting level is parsed by a further recursive call with no bound on depth. About 2,000 levels (8 KB of DER) are enough to exhaust a 1.5 MB thread stack, the .NET main-thread default on Windows, and raise a StackOverflowException, which .NET cannot catch and which terminates the whole process; on threads with larger stacks, parse time instead grows quadratically with depth (about 9 seconds of CPU for a 64 KB input). Any path that parses untrusted ASN.1 is exposed, including X.509 certificates and CRLs, CMS/PKCS#7, PKCS#8/PKCS#12, OCSP and TLS Certificate messages.
References
Configurations
History
28 Oct 2026, 14:48
| Type | Values Removed | Values Added |
|---|---|---|
| CVSS |
v2 : v3 : |
v2 : unknown
v3 : 7.5 |
| CPE | cpe:2.3:a:bouncycastle:bc-csharp:*:*:*:*:*:*:*:* | |
| First Time |
Bouncycastle bc-csharp
Bouncycastle |
|
| References | () https://github.com/bcgit/bc-csharp/commit/89c81b0da7fe11cd70013285560bbc472cb73901 - Patch | |
| References | () https://github.com/bcgit/bc-csharp/commit/b99f4e3dcea05b57becc79dfa6ad91a54c778d65 - Patch | |
| References | () https://github.com/bcgit/bc-csharp/wiki/CVE-2026-103600 - Patch, Vendor Advisory |
02 Oct 2026, 08:17
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-10-02 08:17
Updated : 2026-10-28 14:48
NVD link : CVE-2026-103600
Mitre link : CVE-2026-103600
CVE.ORG link : CVE-2026-103600
JSON object : View
Products Affected
bouncycastle
- bc-csharp
CWE
CWE-674
Uncontrolled Recursion