{"id":"CVE-2026-63575","summary":"PKCS#12 key derivation loops about 2^32 times on a zero or negative iteration count","details":"Loop with unreachable exit condition in the PKCS#12 key derivation (Pkcs12ParametersGenerator) in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows an attacker who can supply a PKCS#12 (PFX) file, or a PKCS#8 encrypted private key that uses a PKCS#12 password-based encryption algorithm, to cause a denial of service through CPU exhaustion via an iteration count of zero or below, because the derivation loop ran until its counter equalled the count, so for such a count it wrapped through about 2^32 iterations before the MAC or the password could be checked. A 75-byte PFX file with a negative MacData iteration count kept Pkcs12Store.Load busy for many minutes.","modified":"2026-10-04T02:46:54.766214502Z","published":"2026-10-02T07:06:31.876Z","database_specific":{"cwe_ids":["CWE-835"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63575.json","cna_assigner":"bcorg"},"references":[{"type":"WEB","url":"https://www.nuget.org/packages/BouncyCastle.Cryptography"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63575.json"},{"type":"ADVISORY","url":"https://github.com/bcgit/bc-csharp/wiki/CVE-2026-63575"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-63575"},{"type":"FIX","url":"https://github.com/bcgit/bc-csharp/commit/0c7a6dfd64c4a479577e35a728a766721b79aba7"},{"type":"FIX","url":"https://github.com/bcgit/bc-csharp/commit/7c0ed15f9783c9595b1a53f3900136461fd944f4"},{"type":"PACKAGE","url":"https://github.com/bcgit/bc-csharp"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/bcgit/bc-csharp","events":[{"introduced":"0"},{"fixed":"4007498b13582d90ee1eda5d9920c324428b98b3"},{"fixed":"0c7a6dfd64c4a479577e35a728a766721b79aba7"},{"fixed":"7c0ed15f9783c9595b1a53f3900136461fd944f4"}],"database_specific":{"source":["DESCRIPTION","REFERENCES"],"extracted_events":[{"introduced":"0"},{"fixed":"2.7.0"}]}}],"versions":["release-1.9.0","release-1.8.10","release-1.8.8","release-1.8.7","release-1.8.6","release-1.8.5","release-1.8.4","release-1.8.3","release-1.8.2","release-1.8.1","release-1.8.0","release-1.8.0-RC.3","release-1.8.0-RC.2","release-1.8.0-RC.1","release-1.8.0-beta.4","release-1.8.0-beta.3","release-1.8.0-beta.2","release-1.8.0-beta.1"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-63575.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N"}]}