{"schema":"threatline.record/2","record":{"id":"CVE-2026-63570","aliases":[],"summary":"Pkcs12Store.GetCertificateChain loops forever on cyclic issuer links","details":"Loop with unreachable exit condition in Pkcs12Store.GetCertificateChain in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows an attacker who can supply a crafted PKCS#12 file to an application that loads it and requests a key entry's certificate chain to cause a denial of service, in which the call never returns and consumes CPU and memory until an OutOfMemoryException, via certificates whose issuer links form a cycle, for example two certificates whose AuthorityKeyIdentifier extensions each identify the other's public key. This happens because the chain-building loop stops only when no issuer is found or a certificate links to itself, and keeps no record of certificates already visited. The key-identifier links are followed without checking signatures.","categories":["Unclassified"],"product":"bc-csharp","vendor":"Legion of the Bouncy Castle Inc.","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-63570","source_modified_at":"2026-10-02T19:13:27.192Z","fetched_at":"2026-10-23T18:52:38.922436Z","product":"bc-csharp","vendor":"Legion of the Bouncy Castle Inc.","versions":[{"status":"affected","version":"0","lessThan":"2.7.0","versionType":"semver"}],"defaultStatus":"unaffected"}],"fixed_versions":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-63570","source_modified_at":"2026-10-02T19:13:27.192Z","fetched_at":"2026-10-23T18:52:38.922436Z","package":{"name":"bc-csharp","ecosystem":null},"version":"2.7.0","basis":"first unaffected version stated in the CVE record"}],"cvss":7.1,"severity":"High","kev":{"listed":false},"epss":{"probability":0.00213,"percentile":0.11091,"score_date":"2026-10-23"},"published_at":"2026-10-02T07:01:18.029Z","modified_at":"2026-10-02T19:13:27.192Z","provenance":[{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-63570","fetched_at":"2026-10-23T18:52:38.922436Z","source_modified_at":"2026-10-02T19:13:27.192Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-63570","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23"}],"sources":["CVE List","EPSS"],"references":[{"source":"CVE List","url":"https://github.com/bcgit/bc-csharp/wiki/CVE-2026-63570","tags":["vendor-advisory"]},{"source":"CVE List","url":"https://github.com/bcgit/bc-csharp/commit/1b8fad04df4953230c9951c57678ee45c8aead85","tags":["patch"]}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","cvss_source":"CVE List","ssvc":{"exploitation":"none","automatable":"no","technical_impact":"partial","assessed_at":"2026-10-02T19:11:44.476831Z"},"classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":null,"confidence":"unknown","reviewed":false},"change_timestamp":"2026-10-02T19:13:27.192Z","content_hash":"cbf5431a66d99fe06888001ade60e3b21e70bb6ce80973f74c4ecc6667b215f9"}}