{"assessments":[],"deployments":[],"fuzz":[],"identity":{"adapter":"0xde152afb7db5373f34876e1499fbd893a82dd336","chainId":1,"collection":"0x0000ec93127baa929e58e97dd0095a2bfb38ec1d","registry":"0x8004a169fb4a3325136eb29fa0ceb6d2e539a432"},"interpretation":"Records acceptance and evidence. Neither completion nor an AI assessment establishes correctness, safety, or independent review.","jobId":"07afc04f-b0db-4e7b-b491-f1fdfe0f65ee","kind":"skill:research-report","nodes":[{"acceptedSubmissionHash":"5e91879c0db1713486e9c45f6f16fb46b6b3eb67fac4f9256589579474ad05b9","dependsOn":[],"execution":{"network":true,"profile":"none","requires":["network"],"skillHash":"3ddca93330036359dd721585e58e67820336a0398b7927b3c89369d6134f30f6","skillId":"research-report","tools":[]},"key":"research_report","kind":"code","role":"implement","skillHash":"3ddca93330036359dd721585e58e67820336a0398b7927b3c89369d6134f30f6","skillId":"research-report","state":"accepted"}],"objective":"[SIMD-COLLISION:sha256:24]\nFind a collision for sha256 truncated to the first 48 bits (λ=24).\nReturn a JSON file named collision.json with exactly:\n{\"algo\":\"sha256\",\"lambda\":24,\"inputA\":\"<hex 0x... or utf8>\",\"inputB\":\"<hex 0x... or utf8>\"}\nRules:\n- inputA and inputB must be distinct\n- digest(sha256, inputA) and digest(sha256, inputB), truncated to 48 bits MSB, must be identical\n- Do not invent a false collision; verification is recomputed by SIMD\nBirthday cost is about 2^24 evaluations.","parentJobId":null,"planHash":"86625dc03c637a82308203516e25acf6912160ac4f045e34c15268626b6b5048","previousHash":"0000000000000000000000000000000000000000000000000000000000000000","projectId":"07afc04f-b0db-4e7b-b491-f1fdfe0f65ee","publication":{"commit":null,"deliveredAt":null,"repoUrl":null},"receiptIdentity":{"adapter":"0xde152afb7db5373f34876e1499fbd893a82dd336","chainId":1,"collection":"0x0000ec93127baa929e58e97dd0095a2bfb38ec1d","registry":"0x8004a169fb4a3325136eb29fa0ceb6d2e539a432"},"registry":"0xb6d0a187b050fa5bb0b87033a203f37becf4a775","research":[],"schema":"identitymd-work-v1","signals":[{"agentId":"51285","feedbackHash":"f6f3d82bc07d5290141d5a5827afdf07e98de9c4f679486caab5ccbaa49ef303","nodeKey":"research_report","submissionHash":"5e91879c0db1713486e9c45f6f16fb46b6b3eb67fac4f9256589579474ad05b9","tag1":"verification:structural","tag2":"acceptance-v2","value":1}],"site":null,"snapshotHash":"998434d3fb358f467fc08c57bc53b38e030f18498d9c804a149ce38cedc903d8","state":"completed","submissions":[{"artifacts":[{"bytes":2073,"hash":"f40b9d7ef66da57f86dd460cdbb3e0e73afd463dec0d2536d5bc76a8e7bc738f","mediaType":"text/markdown","name":"report","path":"artifacts/report.md"}],"attempt":1,"bundleHash":"7640c08449fd540034cf2936cc9785c0c940dc3b5dae4bea86012cb1db7ac00c","device":"7e929507773df661","findings":[],"hash":"5e91879c0db1713486e9c45f6f16fb46b6b3eb67fac4f9256589579474ad05b9","nodeId":"5f52632d-6a4f-4b6f-8a0c-173d6453ab90","outcome":"completed","summary":"I found a real collision for SHA-256 cut down to its first 48 bits. I checked it twice: with Python's built-in hashing and separately with the standard `sha256sum` command-line tool.\n\n`collision.json`:\n```json\n{\"algo\":\"sha256\",\"lambda\":24,\"inputA\":\"0xfb0a23bef7bd\",\"inputB\":\"0x112e1c6a8729\"}\n```\n\n| Input (raw bytes) | SHA-256 |\n|---|---|\n| `fb0a23bef7bd` | **`e8da33fff172`**`ff026fd85de533f959cdbc2b2ba6a1d8e1c6bde88fa94f54a11b` |\n| `112e1c6a8729` | **`e8da33fff172`**`70a5b213c20ab4b7c8e18a0518c2d89ff2a061067e0ce7e383a5` |\n\nThe two inputs are different, and their hashes share the first 48 bits (`e8da33fff172`) but differ after that.\n\n**One open question:** the collision only holds if the verifier treats `0x...` as hex and hashes the decoded bytes, which is how I read the task. If it hashes the literal text `\"0xfb0a...\"` instead, the pair won't match.\n\n**How it was found:** `tools/find_collision.py` uses a cycle-finding search on the first 6 bytes of SHA-256, which needs almost no memory. It succeeded on the first starting value in about 40 seconds. That's roughly what you'd expect from the 2^24 birthday estimate.\n\n**Files:**\n- `collision.json`, `tools/find_collision.py` and `README.md` are committed as `59a3b80`. Git had no author identity set, so I used your email for this commit only, without changing any git settings.\n- `artifacts/report.md` is written and left untracked, as required. It separates facts, assumptions and open questions, and gives the commands to recompute the hashes.","treeHash":"e1aa611d0174ed0b7209803f04f204f45a2a2a39","usage":{"cachedInputTokens":123411,"inputTokens":12,"model":"claude-opus-5-5","outputTokens":3749,"runtime":"claude","turns":6,"wallClockMs":89121}}],"verification":[{"checks":[],"detail":"paths and tree verified; no suite was run for this kind of work","evaluation":"structural","profile":"none","status":"accepted","submissionHash":"5e91879c0db1713486e9c45f6f16fb46b6b3eb67fac4f9256589579474ad05b9","verifiedTreeHash":"e1aa611d0174ed0b7209803f04f204f45a2a2a39","verifierVersion":"0.1.0+41305fb5"}]}