CVE-2026-77470 Business logic in Lychee
An attacker can manipulate payment amounts in the webshop checkout to purchase items at a lower price than intended.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-77470?
CVE-2026-77470 is a high-severity vulnerability in LycheeOrg Lychee, published on 15 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Lychee is a free, open-source photo-management tool. Prior to 7.7.1, the Supporter or Pro webshop POST /api/v2/Shop/Checkout/Process flow accepts an unrestricted additional_data array and CheckoutService::preparePurchaseParameters() merges it after server-computed purchase parameters. Because later string keys overwrite earlier keys, an unauthenticated buyer can replace amount, currency, returnUrl, cancelUrl, or transactionId before CheckoutService::processPayment() passes the parameters to a non-PayPal Omnipay gateway. An attacker can therefore make a gateway accept a successful payment for an attacker-selected amount and obtain auto-fulfilled goods while underpaying the merchant. The issue requires an enabled webshop, a purchasable item, and an affected Omnipay gateway. This issue is fixed in version 7.7.1.
Which versions are affected by CVE-2026-77470?
How do I fix CVE-2026-77470?
No fix has been published for CVE-2026-77470 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-77470 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-77470 exists.
Sources
Also known as GHSA-476v-jr53-8rxc.