CVE-2024-24559
mediumpriority · track · 21OT risk · elevatedEPSS 0.003 · 17 %ileEUUSEPSS · scored 2026-10-27
Vyper is a Pythonic Smart Contract Language for the EVM. There is an error in the stack management when compiling the `IR` for `sha3_64`. Concretely, the `height` variable is miscalculated. The vulnerability can't be triggered without writing the `IR` by hand (that is, it cannot be triggered from regular vyper code). `sha3_64` is used for retrieval in mappings. No flow that would cache the `key` was found so the issue shouldn't be possible to trigger when compiling the compiler-generated `IR`. This issue isn't triggered during normal compilation of vyper code so the impact is low. At the time of publication there is no patch available.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–medium · 3.7–5.3
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (5)
Products and version ranges known to be affected.
advisories (2)
Vendor and ecosystem advisories describing this.
- GHSA-6845-xw22-ffxvVyper sha3 codegen bug2024-02-05ghsa · osvUS
### Summary There is an error in the stack management when compiling the `IR` for `sha3_64`. Concretely, the `height` variable is miscalculated. The 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). ### Details To compile `sha3_64`, the `arg[0]` and `arg[1]` have to be compiled: https://github.com/vyperlang/vyper/blob/c150fc49ee9375a930d177044559b83cb95f7963/vyper/ir/compile_ir.py#L585-L586 As 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. `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`. ### PoC Suppose the following hand-written IR: ```lisp (with _loc (with val 1 (with key 2 (sha3_64 val key))) (seq (sstore _loc (with x (sload _loc) (with ans (add x 1) (seq (assert (ge ans x)) ans)))))) ``` after compilation: ``` the generated bytecode: 6001600281806020525f5260405f2090509050805460018101818110610026579050815550005b5f80fd 0000 60 PUSH1 0x01 0002 60 PUSH1 0x02 0004 81 DUP2 0005 80 DUP1 *********** bad code here!!!!!! 0006 60 PUSH1 0x20 0008 52 MSTORE ``` It can be seen that the second `DUP` will dup the item on the top of the stack which is incorrect. ### Patches Patched in https://github.com/vyperlang/vyper/pull/4063. ### Impact Versions 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.
- PYSEC-2024-1472024-02-05vendor · osvUS
Vyper is a Pythonic Smart Contract Language for the EVM. There is an error in the stack management when compiling the `IR` for `sha3_64`. Concretely, the `height` variable is miscalculated. The vulnerability can't be triggered without writing the `IR` by hand (that is, it cannot be triggered from regular vyper code). `sha3_64` is used for retrieval in mappings. No flow that would cache the `key` was found so the issue shouldn't be possible to trigger when compiling the compiler-generated `IR`. This issue isn't triggered during normal compilation of vyper code so the impact is low. At the time of publication there is no patch available.
also known as (6)
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sources
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references (7)
External citations — patches, advisories, analysis.
- https://cxsecurity.com/cveshow/CVE-2024-24559/cnnvd
- https://github.com/vyperlang/vyper/blob/c150fc49ee9375a930d177044559b83cb95f7963/vyper/ir/compile_ir.py#L585-L586cnnvd
- https://github.com/vyperlang/vyper/security/advisories/GHSA-6845-xw22-ffxvcnnvd
- https://github.com/vyperlang/vyper/blob/c150fc49ee9375a930d177044559b83cb95f7963/vyper/ir/compile_ir.py#L585-L586enisa_euvd
- https://github.com/vyperlang/vyper/security/advisories/GHSA-6845-xw22-ffxvenisa_euvd
- https://github.com/vyperlang/vyper/blob/c150fc49ee9375a930d177044559b83cb95f7963/vyper/ir/compile_ir.py#L585-L586Productnvd
- https://github.com/vyperlang/vyper/security/advisories/GHSA-6845-xw22-ffxvVendor Advisorynvd
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