{"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":"4965bae1-8083-43d7-9d5f-35c906d5fe6f","kind":"skill:research-report","nodes":[{"acceptedSubmissionHash":"e54691b2c365640e20ce0456c6d8b3cdcc06e5a58f3ba959071e5ca140df88af","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:keccak256:24]\nFind a collision for keccak256 truncated to the first 48 bits (λ=24).\nReturn a JSON file named collision.json with exactly:\n{\"algo\":\"keccak256\",\"lambda\":24,\"inputA\":\"<hex 0x... or utf8>\",\"inputB\":\"<hex 0x... or utf8>\"}\nRules:\n- inputA and inputB must be distinct\n- digest(keccak256, inputA) and digest(keccak256, 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":"8ac951502b3ce9b5f98ad28015f6561157f756ecc5470fcb647a3f9e51c585aa","previousHash":"0000000000000000000000000000000000000000000000000000000000000000","projectId":"4965bae1-8083-43d7-9d5f-35c906d5fe6f","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":"51093","feedbackHash":"9d0933a717cf724106204c419b1cd6446eaeb38c408690cb0d2fb7fcd05862c1","nodeKey":"research_report","submissionHash":"e54691b2c365640e20ce0456c6d8b3cdcc06e5a58f3ba959071e5ca140df88af","tag1":"verification:structural","tag2":"acceptance-v2","value":1}],"site":null,"snapshotHash":"28e24a75c922dfa0f365723254c1d832cd9848fe52018c3fcc2080cac5dccd44","state":"completed","submissions":[{"artifacts":[{"bytes":3083,"hash":"0db02bb2586bd6190eb7788c228cc782fabcfc414949f270554f85ace83c68dc","mediaType":"text/markdown","name":"report","path":"artifacts/report.md"}],"attempt":1,"bundleHash":"ca86000af95f4038d1188a3e79ac2e88d513b03112fc839a3c61bb48908bc842","device":"575a41a8798743c2","findings":[],"hash":"e54691b2c365640e20ce0456c6d8b3cdcc06e5a58f3ba959071e5ca140df88af","nodeId":"f3dd34c6-8053-450b-ba7a-d843860ef76f","outcome":"completed","summary":"I'll find a 48-bit truncated keccak256 collision via birthday search (~2^24 evaluations). First, let me check the environment for available tooling.Empty repo, Python 3.12, gcc available, no pycryptodome. For ~2^24 keccak evaluations I'll write a self-contained C implementation (proper Keccak-256, 0x01 domain padding). Checking resources first.Empty repo, 2 cores, ~6.5GB free RAM, and pip is PEP-668-blocked. Plan:\n\n1. Write a self-contained C keccak256 (Keccak padding `0x01`, not SHA3 `0x06`) birthday search in `test/scratch/`, validate against known vectors.\n2. Run the ~2^24 search; store digests in an open-addressed table.\n3. Independently verify the pair with pycryptodome (in a venv).\n4. Write `collision.json` + `artifacts/report.md`, leave outputs untracked.Implementation validated against both known keccak256 test vectors. The search is running in the background — waiting for it to finish.The search hit a false positive: byte 0 differs (`7a` vs `7d`) — only 40 bits match. Bug: a displaced entry from linear probing can land in a slot whose index it doesn't own, and my tag check (top 22 bits) didn't re-verify the low bits. Fix: on a tag match, recompute the stored candidate's digest and compare all 48 bits; keep probing on mismatch.Now rebuild and rerun, and set up a pycryptodome venv in parallel for independent verification.pycryptodome is installed and confirms the same keccak256 vector (`4e03657a...` for \"abc\"), so my C implementation and the reference library agree on Keccak padding. Waiting for the search.Collision found after ~29.1M evaluations — first 6 bytes `181e3ab6fb1c` match on both. Verifying independently with pycryptodome.Verified independently — `181e3ab6fb1c` matches on both inputs. Writing deliverables: `collision.json` (untracked named output), `artifacts/report.md`, and I'll commit the finder source under `tools/` for reproducibility.Committing only the tool source, leaving the named outputs untracked.`artifacts/` and `test/scratch/` are already excluded via `.git/info/exclude` — good. Git identity isn't configured; I'll use per-command `-c` flags (doesn't modify any config files) to commit the tool source.Final check: validate `collision.json` content and re-verify digests directly from the file.Done. Collision found and verified.\n\n**Result** — `collision.json` (repo root, untracked as required):\n```json\n{\"algo\":\"keccak256\",\"lambda\":24,\"inputA\":\"imd-c24-00000000007712cc\",\"inputB\":\"imd-c24-0000000001bc5f42\"}\n```\nBoth inputs are distinct ASCII strings; keccak256 (Keccak `0x01` padding) truncated to 48 bits gives `181e3ab6fb1c` for each.\n\n**How it was produced**\n- Self-contained C birthday search (`tools/find_collision.c`, committed): Keccak-f[1600], rate 136B, open-addressed table of 2^26 slots; found after 29,122,371 evaluations (~1.7×2^24, consistent with birthday cost).\n- One bug was caught and fixed mid-run: linear-probing displacement caused a false tag match (only 40 bits equal); the check now recomputes and compares the full 48-bit prefix before accepting.\n- Implementation validated against published keccak256 vectors (`\"\"` and `\"abc\"`), and the pair independently re-verified with PyCryptodome `Crypto.Hash.keccak`.\n\n**Deliverables**\n- `collision.json` — answer, untracked.\n- `artifacts/report.md` — method, evidence, facts vs. inferences vs. uncertainty.\n- `artifacts/README.md` — scope and limits.\n- `tools/find_collision.c` — tracked source for reproducibility.\n\nOne noted caveat in the report: \"keccak256\" is interpreted as original Keccak (not NIST SHA3-256), matching the task's explicit naming.\n","treeHash":"f2adeb3ff0dffb72668d70ed2898602e36b43ed3","usage":{"cachedInputTokens":0,"inputTokens":0,"model":"swe-2-high","outputTokens":0,"runtime":"codex","turns":1,"wallClockMs":185557}}],"verification":[{"checks":[],"detail":"paths and tree verified; no suite was run for this kind of work","evaluation":"structural","profile":"none","status":"accepted","submissionHash":"e54691b2c365640e20ce0456c6d8b3cdcc06e5a58f3ba959071e5ca140df88af","verifiedTreeHash":"f2adeb3ff0dffb72668d70ed2898602e36b43ed3","verifierVersion":"0.1.0+41305fb5"}]}