{"id":"CVE-2026-103604","title":"Inefficient algorithmic complexity in X.509 distinguished name string conversion (X509Name.ToString and IetfUtilities.ValueToString) in Legion of the Bouncy Castle Inc","summary":"Inefficient algorithmic complexity in X.509 distinguished name string conversion (X509Name.ToString and IetfUtilities.ValueToString) in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows a remote unauthenticated attacker to c…","severity":"high","cvss":8.7,"cvssVector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","cwe":["CWE-407"],"vendor":"Legion of the Bouncy Castle Inc.","product":"BouncyCastle.Cryptography","affected":["BouncyCastle.Cryptography < 2.7.0"],"published":"2026-10-02","updated":"2026-10-02","sourceUpdated":"2026-10-02T08:17:00.980","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-103604","references":[{"url":"https://github.com/bcgit/bc-csharp/commit/bd03e38bbb49db5be33f4463fc40997400c545cc","label":"91579145-5d7b-4cc5-b925-a0262ff19630"},{"url":"https://github.com/bcgit/bc-csharp/wiki/CVE-2026-103604","label":"91579145-5d7b-4cc5-b925-a0262ff19630"}],"tags":["nvd","cve.org"],"cvssSource":"cna","ingestedAt":"2026-10-02T08:14:06.225Z","slug":"CVE-2026-103604","body":"## Overview\n\nInefficient algorithmic complexity in X.509 distinguished name string conversion (X509Name.ToString and IetfUtilities.ValueToString) in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows a remote unauthenticated attacker to cause a denial of service through CPU exhaustion via a certificate, CRL, certification request or other structure whose name contains a long attribute value made up of characters that must be escaped, such as commas, or of leading or trailing spaces, because each escaping backslash was inserted into the buffer being scanned, so the work grew quadratically with the length of the value. Applications are exposed when they convert such a name to a string, for example to log or display it, or compare it with IetfUtilities.RdnAreEqual, as PKIX path validation does for directoryName name constraints.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":48,"depthScoreParts":{"impact":47.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}