How severe is CVE-2026-57959?

CVE-2026-57959 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2026-57959 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (9th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-57959?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2026-57959 published?

CVE-2026-57959 was published on 2026-06-29.

CVE-2026-57959

CVE-2026-57959 is a medium-severity vulnerability with a CVSS 3.x base score of 5.9. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-367.

Key facts

Severity: Medium (CVSS 3.x base score 5.9)
CVSS v4: 8.2
EPSS exploit prediction: 0% (9th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-367
Published: 2026-06-29
Last modified: 2026-06-29

Description

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.

Frequently asked questions

What is 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.
How severe is CVE-2026-57959?: CVE-2026-57959 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2026-57959 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (9th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-57959?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2026-57959 published?: CVE-2026-57959 was published on 2026-06-29.

References

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