This vulnerability in Red Hat Quay's Stripe billing webhook handler arises from improper verification of the Stripe-Signature header, allowing unauthenticated attackers to forge billing events by sending crafted JSON requests to the /webhooks/stripe endpoint. Successful exploitation can lead to unauthorized resetting of build quotas for namespaces and unsolicited billing emails to administrators, impacting resource availability and user experience. The flaw is present even when billing is disabled, though mitigated in self-hosted environments using FakeStripe. Red Hat has not yet provided an official patch or fix. The recommended mitigation is to restrict network access to the /webhooks/stripe endpoint to only trusted Stripe IP addresses or block it entirely if Stripe billing integration is not used. This mitigation may require service restarts and could temporarily impact Quay availability.

The vulnerability allows unauthenticated attackers to forge billing events, which can reset a namespace's build quota to its maximum without authorization and cause unsolicited billing emails to be sent to namespace administrators. This affects the integrity of billing and quota management but does not impact confidentiality or availability directly. The flaw exists even if billing is disabled, though its impact is reduced in self-hosted deployments using FakeStripe.

No official patch or fix is currently available for this vulnerability. To mitigate the risk, restrict network access to the /webhooks/stripe endpoint in Red Hat Quay by configuring network firewalls to allow connections only from trusted Stripe IP addresses. If Stripe billing integration is not used, block access to this endpoint entirely. Apply network changes carefully and reload or restart services as necessary, noting that this may temporarily impact Quay service availability.