Vulnerability in Hieventsdev Hi.events
CVE-2026-57959
Hi.Events through 1.9.0 contains a promo code validation vulnerability where reservation validates usage count before asynchronous UpdateEventStatisticsJob increments it, allowing attackers to redeem limited promo codes unlimited times. Attackers can sequentially reserve multiple orders with the same restricted promo code, each reading order_usage_count=0 and passing validation, then complete them all at discounted prices without concurrent requests.
Vulnerability class: TOCTOU (Time-of-Check to Time-of-Use)
EPSS: 0.002 (9.3th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N.
Affected products
- Hieventsdev Hi.events — versions 0
Weakness classification (CWE)
References
- disclosure@vulncheck.com (issue-tracking)
- disclosure@vulncheck.com (third-party-advisory)
Frequently asked questions
- What is CVE-2026-57959?
- CVE-2026-57959 is a medium-severity vulnerability in Hieventsdev Hi.events, classified under Time-of-check Time-of-use (TOCTOU) Race Condition. CVSS score: 5.9/10. Published 2026-06-29.
- How severe is CVE-2026-57959?
- Medium severity. CVSS v3 base score is 5.9 out of 10.