{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-48100","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","state":"PUBLISHED","assignerShortName":"GitHub_M","dateReserved":"2026-05-20T18:40:45.835Z","datePublished":"2026-09-28T16:43:06.401Z","dateUpdated":"2026-09-28T17:27:18.467Z"},"containers":{"cna":{"title":"Payy: agg_agg trailing message slots are unconstrained and allow forged burn messages","problemTypes":[{"descriptions":[{"cweId":"CWE-349","lang":"en","description":"CWE-349: Acceptance of Extraneous Untrusted Data With Trusted Data","type":"CWE"}]}],"metrics":[{"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"HIGH","vulnAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","baseScore":8.7,"baseSeverity":"HIGH","vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N","version":"4.0"}}],"references":[{"name":"https://github.com/polybase/payy/security/advisories/GHSA-fhxc-63vg-9gwr","tags":["x_refsource_CONFIRM"],"url":"https://github.com/polybase/payy/security/advisories/GHSA-fhxc-63vg-9gwr"}],"affected":[{"vendor":"polybase","product":"payy","versions":[{"version":"< 1.3.0","status":"affected"}]}],"providerMetadata":{"orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M","dateUpdated":"2026-09-28T16:43:06.401Z"},"descriptions":[{"lang":"en","value":"Payy is an Ethereum L2 zk-rollup for privacy preserving and regulatory compliant transactions. Prior to version 1.3.0, agg_agg forwards the compacted message stream from its inner proofs into a public messages: [Field; 1000] array, but it never checks that the unused tail of the outer array is zero. A registered prover can build a valid agg_final proof for an approved rollup block while inserting an extra burn message after the real messages. RollupV1.verifyRollup() then parses that public input as a normal burn and transfers USDC from the rollup contract to the attacker. This is a severe circuit soundness failure: the proof system accepts a public statement whose messages array is not fully derived from the verified inner proofs. On the current deployment, verifyRollup() is restricted to the existing allowlisted prover, so a fresh public caller cannot submit the invalid proof directly. That gate limits who can reach L1 today; it does not make the circuit statement sound. The issue becomes permissionless under the prover model described in the Payy whitepaper. Section 3.3.2 states: \"To join as a prover, the prover is required to submit a small stake\", and Section 3.3.1 states that if a prover fails to submit, \"other nodes can submit the block proof instead.\" In that model, an attacker only needs to become a registered prover and use public validator approval data for an already approved block. This issue has been patched in version 1.3.0."}],"source":{"advisory":"GHSA-fhxc-63vg-9gwr","discovery":"UNKNOWN"}},"adp":[{"references":[{"url":"https://github.com/polybase/payy/security/advisories/GHSA-fhxc-63vg-9gwr","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-09-28T17:20:42.562536Z","id":"CVE-2026-48100","options":[{"Exploitation":"poc"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-09-28T17:27:18.467Z"}}]}}