{"id":"CVE-2026-63575","title":"Loop with unreachable exit condition in the PKCS#12 key derivation (Pkcs12ParametersGenerator) in Legion of the Bouncy Castle Inc","summary":"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 priva…","severity":"high","cvss":7.1,"cvssVector":"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","cwe":["CWE-835"],"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":"2026-10-02T08:17:02.643","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-63575","references":[{"url":"https://github.com/bcgit/bc-csharp/commit/0c7a6dfd64c4a479577e35a728a766721b79aba7","label":"91579145-5d7b-4cc5-b925-a0262ff19630"},{"url":"https://github.com/bcgit/bc-csharp/commit/7c0ed15f9783c9595b1a53f3900136461fd944f4","label":"91579145-5d7b-4cc5-b925-a0262ff19630"},{"url":"https://github.com/bcgit/bc-csharp/wiki/CVE-2026-63575","label":"91579145-5d7b-4cc5-b925-a0262ff19630"}],"tags":["nvd","cve.org"],"cvssSource":"cna","ingestedAt":"2026-10-02T08:14:06.228Z","slug":"CVE-2026-63575","body":"## Overview\n\nLoop 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.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":39,"depthScoreParts":{"impact":39.1,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}