{"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":"b26cb4c9-eda6-4665-b4c8-15673dacffdf","kind":"skill:research-report","nodes":[{"acceptedSubmissionHash":"50dc0746e9a50e46acb290378a7f4532099b15016c2bf315a66e5694333c3313","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:ripemd160:24]\nFind a collision for ripemd160 truncated to the first 48 bits (λ=24).\nReturn a JSON file named collision.json with exactly:\n{\"algo\":\"ripemd160\",\"lambda\":24,\"inputA\":\"<hex 0x... or utf8>\",\"inputB\":\"<hex 0x... or utf8>\"}\nRules:\n- inputA and inputB must be distinct\n- digest(ripemd160, inputA) and digest(ripemd160, 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":"db8cf59269792af61e6af2b5ee3f86a9745dd031d74535fb14290fe873f6a5ff","previousHash":"0000000000000000000000000000000000000000000000000000000000000000","projectId":"b26cb4c9-eda6-4665-b4c8-15673dacffdf","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":"51364","feedbackHash":"aa4e3c5cfbad1ffc1bd596dfc7a3de67cea5fb765c28ab08e94278348fe9ac15","nodeKey":"research_report","submissionHash":"50dc0746e9a50e46acb290378a7f4532099b15016c2bf315a66e5694333c3313","tag1":"verification:structural","tag2":"acceptance-v2","value":1}],"site":null,"snapshotHash":"ce447bd4c7a5f39124cff636d356f2a8c61f243af6e48252cfaa8edc9c4173d9","state":"completed","submissions":[{"artifacts":[{"bytes":2563,"hash":"6bf007e9f8b51dff75eeb68f4f15392f43d74f8640c32899f6d435388ede9a09","mediaType":"text/markdown","name":"report","path":"artifacts/report.md"}],"attempt":1,"bundleHash":"814b3b77f6b38cf1c7442510e506384211df390d15cd8db7273dd38b31953aa2","device":"71a21284629e9f1b","findings":[],"hash":"50dc0746e9a50e46acb290378a7f4532099b15016c2bf315a66e5694333c3313","nodeId":"1fdc7c48-ef8e-4500-95b6-2c3517f8464e","outcome":"completed","summary":"I found a real collision and checked it with two separate RIPEMD-160 implementations.\n\n**Answer** (`collision.json`, committed):\n```json\n{\"algo\":\"ripemd160\",\"lambda\":24,\"inputA\":\"imd-22739628\",\"inputB\":\"imd-33541843\"}\n```\n\n| Input (UTF-8) | RIPEMD-160 |\n|---|---|\n| `imd-22739628` | **3318dbb891e7**348a4a38e96570bb418d9a5d70da |\n| `imd-33541843` | **3318dbb891e7**c6f83d3adea4e0221a7ac64abcc3 |\n\n**What was checked:**\n- The first 48 bits (`0x3318dbb891e7`) match, the two inputs are different, and the full 160-bit hashes are different.\n- Python's `hashlib` and the `openssl dgst -ripemd160` command give the same hashes for both inputs.\n- The hash function gives the published result for an empty input.\n\n**How it was found:** `tools/find_collision.py` hashes `imd-0`, `imd-1`, … and keeps a lookup table until two inputs share the same first 48 bits. It took 33.5M hashes and about 170 seconds. That's about 1.6 times the expected number for a 48-bit birthday search (about 2.1×10⁷), which is normal spread for a single run and doesn't suggest anything wrong with the hash.\n\n**Assumptions and limits** (also written up in the report):\n- I took \"first 48 bits, MSB\" to mean the first 6 bytes of the standard digest.\n- I assumed inputs without a `0x` prefix are hashed as their UTF-8 bytes, with no trailing newline.\n- I haven't seen how the verifier actually reads these values, and no one else has reviewed the work.\n\n**Files:**\n- `artifacts/report.md` is the required report. It's left untracked because Git's local exclude list already ignores `artifacts/`, so it was never committed.\n- Committed: `collision.json`, `README.md` and `tools/find_collision.py`. Git had no author name set, so the commit is attributed to your email using a one-off setting; I didn't change any Git config.","treeHash":"721e8d55c596466bbbea3334fb9273779ef850c1","usage":{"cachedInputTokens":138899,"inputTokens":14,"model":"claude-opus-5-5","outputTokens":4395,"runtime":"claude","turns":7,"wallClockMs":217887}}],"verification":[{"checks":[],"detail":"paths and tree verified; no suite was run for this kind of work","evaluation":"structural","profile":"none","status":"accepted","submissionHash":"50dc0746e9a50e46acb290378a7f4532099b15016c2bf315a66e5694333c3313","verifiedTreeHash":"721e8d55c596466bbbea3334fb9273779ef850c1","verifierVersion":"0.1.0+f8d984f2"}]}