{"id":"CVE-2024-24559","aliases":["GHSA-6845-xw22-ffxv","PYSEC-2024-147"],"url":"https://o3.security/vulnerability/CVE-2024-24559","summary":"Vyper SHA3 code generation bug","details":"### Summary\nThere is an error in the stack management when compiling the `IR` for `sha3_64`. Concretely, the `height` variable is miscalculated.\nThe vulnerability can't be triggered without writing the `IR` by hand. That is, it cannot be triggered from regular vyper code, it can only be triggered by using the `fang` binary directly (this binary used to be called `vyper-ir` prior to v0.3.4).\n\n### Details\nTo compile `sha3_64`, the `arg[0]` and `arg[1]` have to be compiled:\nhttps://github.com/vyperlang/vyper/blob/c150fc49ee9375a930d177044559b83cb95f7963/vyper/ir/compile_ir.py#L585-L586\n\nAs can be seen, after compiling the 0th arg, the `height` variable isn't increased. If new `withargs` are defined in the inner scope, they are manipulated correctly, because both their `height` is off and also the global `height` is off and thus their placement on the stack is computed correctly.\n\n`sha3_64` is used for retrieval in mappings. No flow that would cache the `key` was found, the issue shouldn't be possible to trigger when compiling the compiler-generated `IR`.\n\n### PoC\nSuppose the following hand-written IR:\n```lisp\n(with _loc\n\t(with val 1 \n\t\t(with key 2 \n\t\t\t(sha3_64 val key))) \n\t\t\t\t(seq \n\t\t\t\t\t(sstore _loc \n\t\t\t\t\t(with x (sload _loc) \n\t\t\t\t\t\t(with ans (add x 1) (seq (assert (ge ans x)) ans))))))\n```\nafter compilation:\n```\nthe generated bytecode: 6001600281806020525f5260405f2090509050805460018101818110610026579050815550005b5f80fd\n\n0000    60  PUSH1 0x01\n0002    60  PUSH1 0x02\n0004    81  DUP2\n0005    80  DUP1       *********** bad code here!!!!!!\n0006    60  PUSH1 0x20\n0008    52  MSTORE\n```\n\nIt can be seen that the second `DUP` will dup the item on the top of the stack which is incorrect.\n\n### Patches\nPatched in https://github.com/vyperlang/vyper/pull/4063.\n\n### Impact\nVersions v0.2.0-v0.3.10 were evaluated, and access of the variable with the invalid height is not reachable from IR generated by the vyper front-end. Because the issue isn't triggered during normal compilation of vyper code, the impact is considered low.\n","published":"2024-02-05T21:04:42.056Z","modified":"2026-08-12T03:51:36.425266791Z","cvss":{"score":3.7,"severity":"LOW","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"PyPI","name":"vyper","fixedVersion":"0.4.0"}],"fix":{"url":"https://github.com/vyperlang/vyper/pull/4063","label":"vyperlang/vyper#4063"},"references":[{"type":"WEB","url":"https://github.com/vyperlang/vyper/blob/c150fc49ee9375a930d177044559b83cb95f7963/vyper/ir/compile_ir.py#L585-L586"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/24xxx/CVE-2024-24559.json"},{"type":"ADVISORY","url":"https://github.com/vyperlang/vyper/security/advisories/GHSA-6845-xw22-ffxv"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2024-24559"},{"type":"WEB","url":"https://github.com/vyperlang/vyper/pull/4063"},{"type":"WEB","url":"https://github.com/vyperlang/vyper/commit/d9f9fdadd81a148cbc68f02dbbbcdc0c92fad652"},{"type":"WEB","url":"https://github.com/pypa/advisory-database/tree/main/vulns/vyper/PYSEC-2024-147.yaml"},{"type":"PACKAGE","url":"https://github.com/vyperlang/vyper"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:36.425266791Z"}}