{"schemaVersion":3,"id":"CVE-2026-63578","aliases":[],"status":"published","duplicateOf":null,"title":null,"description":"Allocation of resources without limits in password-based private-key decryption (PbeUtilities.GenerateCipherParameters) in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows an attacker who can supply an encrypted private key, such as a PKCS#8 EncryptedPrivateKeyInfo or \"ENCRYPTED PRIVATE KEY\" PEM file, to cause a denial of service through CPU exhaustion via an iteration count close to 2^31, because the count is taken from the unauthenticated algorithm parameters without an upper bound and the key derivation runs before the password or the data can be checked. PKCS#5 PBES1 and PBES2 (PBKDF2), the PKCS#12 PBE algorithms and CMS password recipients (CmsPbeKey) are affected. Loading PKCS#12 files with Pkcs12Store is covered by CVE-2026-63572, and a zero or negative count with the PKCS#12 algorithms by CVE-2026-63575.","dates":{"published":"2026-10-02T07:08:15.987Z","modified":"2026-10-06T19:31:26.132Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":7.1,"severity":"high","version":"4.0","versionLabel":"v4.0","source":"CVE.org","vector":"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","computed":false,"selection":"backend-summary"},"metrics":[{"version":"4.0","versionLabel":"v4.0","source":"CVE.org","score":7.1,"severity":"high","vector":"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","exploitability":null,"impact":null,"computed":false},{"version":"4.0","versionLabel":"v4.0","source":"NVD","score":7.1,"severity":"high","vector":"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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","exploitability":null,"impact":null,"computed":false}]},"epss":{"probability":0.0033,"percentile":0.24866,"severity":"low","asOf":"2026-10-21T00:00:00.000Z","change":{"pp":null,"baselineDate":null,"baselineScore":null},"history":[{"date":"2026-10-02T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-20T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-21T00:00:00.000Z","score":0.0033,"percentile":0.24866}],"last30":[{"date":"2026-10-02T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-20T00:00:00.000Z","score":0.0033,"percentile":null},{"date":"2026-10-21T00:00:00.000Z","score":0.0033,"percentile":0.24866}]},"kev":{"state":"not-listed","entries":[],"listedCount":0,"totalCatalogs":3,"catalogs":[{"source":"cisa","label":"CISA","listed":false,"entry":null},{"source":"enisa","label":"ENISA","listed":false,"entry":null},{"source":"circl","label":"CIRCL","listed":false,"entry":null}]},"ransomware":{"state":"none-recorded","sources":[]},"exploits":[],"exploitCount":0,"weaknesses":[{"id":"CWE-770","name":"Allocation 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