{"cve":"CVE-2021-43398","nvd":{"published":"2021-11-04T21:15:09.520","modified":"2026-06-17T04:10:55.000","status":"Modified","description":"Crypto++ (aka Cryptopp) 8.6.0 and earlier contains a timing leakage in MakePublicKey(). There is a clear correlation between execution time and private key length, which may cause disclosure of the length information of the private key. This might allow attackers to conduct timing attacks. NOTE: this report is disputed by the vendor and multiple third parties. The execution-time differences are intentional. A user may make a choice of a longer key as a tradeoff between strength and performance. In making this choice, the amount of information leaked to an adversary is of infinitesimal value","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","score":5.3},"cwes":["CWE-203"],"references":["https://cryptopp.com","https://github.com/weidai11/cryptopp/issues/1080","https://github.com/weidai11/cryptopp/issues/1080#issuecomment-996492222","https://cryptopp.com","https://github.com/weidai11/cryptopp/issues/1080"],"products":["cryptopp:crypto\\+\\+"],"source":"nvd","synced_at":"2026-10-19T21:24:39.218183596+00:00"},"epss":{"cve":"CVE-2021-43398","score":0.0207,"percentile":0.81429,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}