{"cve":"CVE-2018-18531","nvd":{"published":"2018-10-19T20:29:00.570","modified":"2026-06-17T01:47:27.823","status":"Modified","description":"text/impl/DefaultTextCreator.java, text/impl/ChineseTextProducer.java, and text/impl/FiveLetterFirstNameTextCreator.java in kaptcha 2.3.2 use the Random (rather than SecureRandom) function for generating CAPTCHA values, which makes it easier for remote attackers to bypass intended access restrictions via a brute-force approach.","cvss_v4":null,"cvss_v3":{"version":"3.0","vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","score":9.8},"cwes":["CWE-330"],"references":["https://github.com/penggle/kaptcha/issues/3","https://github.com/penggle/kaptcha/issues/3"],"products":["kaptcha_project:kaptcha"],"source":"nvd","synced_at":"2026-10-19T20:53:59.789560037+00:00"},"epss":{"cve":"CVE-2018-18531","score":0.01468,"percentile":0.7372,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-8q89-pwhh-7wfq","url":"https://osv.dev/vulnerability/GHSA-8q89-pwhh-7wfq","summary":"Use of Insufficiently Random Values in penggle:kaptcha","modified":"2023-11-08T04:00:05.731213Z","packages":[{"ecosystem":"Maven","name":"com.github.penggle:kaptcha","purl":"pkg:maven/com.github.penggle/kaptcha","ranges":["<=2.3.2"],"fixed":[]}]}],"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."]}