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)
Published · last modified .
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.
EPSS exploit prediction
EPSS: 0.003 (15.6th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 16th percentile — 15.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000
Affected products
- Hieventsdev Hi.events — versions 0
Weakness classification (CWE)
References
- github.com/HiEventsDev/Hi.Events/issues/1223 (issue-tracking)
- www.vulncheck.com/advisories/hi-events-promo-code-max-usage-bypass-via-asynchro… (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.