{"cve":"CVE-2018-12454","nvd":{"published":"2018-06-17T12:29:00.237","modified":"2026-06-17T01:37:48.510","status":"Modified","description":"The _addguess function of a simplelottery smart contract implementation for 1000 Guess, an Ethereum gambling game, generates a random value with publicly readable variables such as the current block information and a private variable (which can be read with a getStorageAt call). Therefore, it allows attackers to always win and get rewards.","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:N/A:N","score":7.5},"cwes":["CWE-338"],"references":["https://medium.com/%40jonghyk.song/attack-on-pseudo-random-number-generator-prng-used-in-1000-guess-an-ethereum-lottery-game-7b76655f953d","https://medium.com/%40jonghyk.song/attack-on-pseudo-random-number-generator-prng-used-in-1000-guess-an-ethereum-lottery-game-7b76655f953d"],"products":["1000guess:1000_guess"],"source":"nvd","synced_at":"2026-10-19T20:51:47.459859389+00:00"},"epss":{"cve":"CVE-2018-12454","score":0.01253,"percentile":0.69459,"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."]}