{"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":"f5006874-86b7-4ab0-a811-8f5829ae1439","kind":"skill:research-report","nodes":[{"acceptedSubmissionHash":"71b75cf6a8235ef929af101b861c5a7b4c16c67ac1e2aa89fbda43180aac6e04","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":"f5006874-86b7-4ab0-a811-8f5829ae1439","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":"51169","feedbackHash":"18056ad605484949e581a80774df8503c5dd1eaac7b606cbdf07ec03a72f79c2","nodeKey":"research_report","submissionHash":"71b75cf6a8235ef929af101b861c5a7b4c16c67ac1e2aa89fbda43180aac6e04","tag1":"verification:structural","tag2":"acceptance-v2","value":1}],"site":null,"snapshotHash":"938b3f92affbf2c1d33728f6dd324799aa770d2c6aa3e1166bcdb1dab29a5361","state":"completed","submissions":[{"artifacts":[{"bytes":2704,"hash":"1c208323200ff3a22d7c5124b3a707faad2c062f8754d2a86f6ae7a0fe33d975","mediaType":"text/markdown","name":"report","path":"artifacts/report.md"}],"attempt":1,"bundleHash":"cad004f8fda4e55b5e21c6f3763f418223aa0dc495b1e1a9461c7153f7486e64","device":"87804e27e9c9f85a","findings":[],"hash":"71b75cf6a8235ef929af101b861c5a7b4c16c67ac1e2aa89fbda43180aac6e04","nodeId":"fa84c81c-5ae1-4219-828d-535549757c42","outcome":"completed","summary":"I found a collision. These two different strings have SHA-256 digests that share the same first 48 bits, `52b3d5bed12a`:\n\n```json\n{\"algo\": \"sha256\", \"lambda\": 24, \"inputA\": \"identitymd-sha256-48-33470631\", \"inputB\": \"identitymd-sha256-48-39003384\"}\n```\n\n- **Checks:** Python's `hashlib`, `openssl dgst -sha256` and `sha256sum` all give the same full digests for both strings. The first 48 bits match, and the digests differ from the 13th hex digit on, as expected. The task's own \"SIMD\" verifier wasn't available here, so I haven't run it.\n- **Encoding:** neither input starts with `0x`, so both should be read as UTF-8 text, as the task's format rule says. Any verifier that adds a trailing newline will not reproduce the match.\n- **How it was found:** I hashed `identitymd-sha256-48-<counter>` for counter = 0, 1, 2, … and stopped at the first repeat in the first 48 bits. That took about 39.0M hashes, 45 seconds and 3.8 GB of memory. The usual expectation is about 21M hashes, and a search runs this long without a collision only about 7% of the time, so this run was unlucky but not suspicious. The search is deterministic, so re-running it gives the same pair.\n\nThe report in `artifacts/report.md` covers the digests, the commands used, the probability figures, and what remains uncertain (mainly the unseen verifier and the λ = 24 vs 48-bit naming). Separate sections cover facts, inferences and uncertainty.\n\n`collision.json`, `README.md`, `tools/find_collision.py` and `tools/verify_collision.py` are committed. `artifacts/report.md` is left untracked as required; `.git/info/exclude` already lists `artifacts/`, so it doesn't appear in `git status`.","treeHash":"281e2562eb4b1413b9471aaec072b05ba7be01c4","usage":{"cachedInputTokens":180750,"inputTokens":16,"model":"claude-opus-5-5","outputTokens":5514,"runtime":"claude","turns":8,"wallClockMs":102413}}],"verification":[{"checks":[],"detail":"paths and tree verified; no suite was run for this kind of work","evaluation":"structural","profile":"none","status":"accepted","submissionHash":"71b75cf6a8235ef929af101b861c5a7b4c16c67ac1e2aa89fbda43180aac6e04","verifiedTreeHash":"281e2562eb4b1413b9471aaec072b05ba7be01c4","verifierVersion":"0.1.0+41305fb5"}]}