CVE-2024-45300: Bypassing promo code limitations with race conditions

Severity: medium (CVSS 5.9 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2024-09-06 · updated 2026-06-17
Weakness: CWE-362

Description

alf.io is an open source ticket reservation system for conferences, trade shows, workshops, and meetups. Prior to version 2.0-M5, a race condition allows the user to bypass the limit on the number of promo codes and use the discount coupon multiple times. In "alf.io", an event organizer can apply price discounts by using promo codes to your events. The organizer can limit the number of promo codes that will be used for this, but the time-gap between checking the number of codes and restricting the use of the codes allows a threat actor to bypass the promo code limit. Version 2.0-M5 fixes this issue.

Affected products

alfio-event alf.io: before 2.0-m5 — fixed in 2.0-m5

How to fix

Upgrade to a fixed version: alfio-event alf.io 2.0-m5. Check the vendor advisory for mitigations.

References

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