KAR-2026-0019 critical 9.1 fixed drill

zkrep drill: operator key of zkrep demo agent B reported compromised

This is a recall drill: Karatum rehearsed the recall mechanism on its own house build. Nothing was compromised. A drill never touches real EAS attestations or real ERC-8004 reputation: where it exercises those steps it revokes a throwaway attestation it created, and publishes feedback that is revoked again when the drill is fixed.

reported
→ triaged
→ confirmed
→ recalled
→ fixed

Facts

Class	Endpoint compromise
Severity	critical (9.1) KAS:1.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N/E:U KAS 1.0, CVSS-v3.1-shaped for agents; the vector is explained in the methodology. High and critical trigger a recall.
Source	operator self-report
Affected	wallet 0xc5a800af3695d5e40cdfc4bed8428789be102428
Disclosure	immediate: the evidence is public record, the operator is Karatum itself or the operator disclosed it
Timeline	reported 2026-10-17 10:01:28 UTC · triaged 2026-10-17 10:01:28 UTC · confirmed 2026-10-17 10:01:28 UTC · recalled 2026-10-17 10:01:37 UTC · closed 2026-10-17 10:01:53 UTC

What happened

DRILL. Karatum rehearses a recall on its own zkrep demo agent B (a testnet wallet acting for house build build-a-careful-v1) to show that a zero-knowledge reputation proof stops being accepted from the next root. Nothing was compromised. The recall is announced in KaratumIncidentLog; the zkrep publisher then publishes a root without B's leaf (immediate), and a proof B made before the recall is rejected on chain. The recall is lifted afterwards.

Evidence

Type	Reference	Note	Checked
url	https://karatum.com/zkrep	the public zkrep demo	in Karatum's records

Links to third-party pages are shown as given by the reporter. A reference marked "in Karatum's records" resolved against our own verdicts, Shield runs, flight records or attestations at intake.

Recall

Confirmed at 2026-10-17 10:01:28 UTC. The first recall transaction was in a block 1.4 s later, the last one after 7.4 s (2 transactions on 2 chains).

Measured as block timestamp (chain clock, 1 s resolution) minus the time the maintainer confirmed (server clock). Base Sepolia blocks are 2 s apart and Ethereum Sepolia blocks 12 s, so those are also the floor of the two numbers. This was a drill: real EAS attestations and ERC-8004 reputation are never touched.

Step	Chain	Result	Transaction
Guard registry revocation (revokeCert) the affected build has no VALID certificate to revoke	Base Sepolia	skipped	—
Guard registry revocation (revokeCert) the affected build has no VALID certificate to revoke	Ethereum Sepolia	skipped	—
EAS attestation revocation drill: EAS revocations are irreversible; real attestations are not touched	—	skipped	—
ERC-8004 feedback drill: no reputation signal is published	—	skipped	—
IncidentLog announcement	Base Sepolia	done	0x6b44f617…ffc5b1 block 48231501
IncidentLog announcement	Ethereum Sepolia	done	0x788456ff…10739a block 11933465

Lifting the recall

IncidentLog status and recall lift on Base Sepolia: 0x02989b66…d8545f
IncidentLog status and recall lift on Ethereum Sepolia: 0xddbe6d6c…7c6a0e

Timeline and operator response

2026-10-17 10:01:28 UTC reported by karatum-operator
2026-10-17 10:01:28 UTC status by maintainer
reported → triaged: operator self-report (drill)
2026-10-17 10:01:28 UTC disclosure by maintainer
2026-10-17 10:01:28 UTC status by maintainer
triaged → confirmed: drill: confirmed by the operator
2026-10-17 10:01:37 UTC status by maintainer
confirmed → recalled
2026-10-17 10:01:37 UTC recall by maintainer
2026-10-17 10:01:53 UTC note by drill
zkrep: root epoch 2 published immediately without agent B's leaf; B's proof made before the recall was rejected on chain (ProofRejected(ROOT_NOT_ACCEPTED))
2026-10-17 10:01:53 UTC status by maintainer
recalled → fixed: drill complete: lifting the recall

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