Wanwu EUVD-2026-97005

The attacker must hold a valid, authenticated, and 'enabled' Wanwu user account (PR:L) on the target instance - unauthenticated exploitation is not possible. No non-default configuration is required: the DELETE /v1/appspace/app/key endpoint in versions before 0.6.3 authorizes solely on the supplied numeric apiId without verifying the caller's userId/orgId ownership. Exploitation requires that target 'legacy' AppKeys exist and that their apiId values are numeric and sequentially enumerable (which the description states they are). Limiting factors: authentication is mandatory, impact is confined to key revocation (denial of service to API/MCP clients) with no data disclosure, and only instances running Wanwu < 0.6.3 are affected.

This is a genuine but moderate-priority authorization flaw (CWE-639, IDOR/BOLA), not a critical issue. The CVSS 4.0 vector (AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:L, 5.3 Medium) is internally consistent with the description: network-reachable, low complexity, but requiring an authenticated low-privilege account (PR:L) - so this is an authenticated insider/cross-tenant attack, not remote-unauthenticated. Impact is limited to Integrity/Availability (VI:L/VA:L) with no confidentiality exposure (VC:N), matching a key-deletion primitive that revokes but does not read secrets. No EPSS score, KEV listing, SSVC decision, or public POC was provided in the input, so exploitation likelihood cannot be quantified from the data; exploitation status is 'no public exploit identified at time of analysis.' The flaw is notably automatable - sequential numeric apiId enumeration against a single DELETE endpoint makes mass key revocation trivial once authenticated - which raises real-world abuse potential above what the 5.3 base score alone suggests, but the authentication requirement and the niche footprint of the product cap overall priority. Key missing signals to verify: EPSS probability and whether VulnCheck or the hackmd writeup includes working exploit code.

A low-privileged but enabled authenticated user on a shared Wanwu instance scripts requests against DELETE /v1/appspace/app/key, iterating sequential numeric apiId values. Because the endpoint checks only that the key ID exists and not that it belongs to the caller's user/org, the attacker revokes legacy AppKeys belonging to other users and organizations, breaking their MCP and OpenAPI integrations until owners reissue keys. No public exploit is identified, but the attack is trivially automatable given the sequential IDs and low complexity.