Vyper sha3 codegen bug

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

3.7 · CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N

EPSS

• CVE-2024-24559: 0.26% estimated exploitation activity in the next 30 days; percentile 17.20 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary There is an error in the stack management when compiling the IR for sha364. 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 sha364, the arg[0] and arg[1] have to be compiled: https://github.com/vyperlang/vyper/blob/c150fc49ee9375a930d177044559b83cb95f7963/vyper/ir/compileir.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. sha364 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…

Published by the source

5 Feb 2024, 19:21 UTC

Last modified by the source

10 Sep 2026, 03:50 UTC

Source last checked

26 Oct 2026, 13:27 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-6845-xw22-ffxv

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-6845-xw22-ffxv

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# Patch Next advisory brief: CVE-2024-24559

Advisory: Vyper sha3 codegen bug
IDs: CVE-2024-24559, GHSA-6845-xw22-ffxv
Record: https://patchnext.com/advisories/cve-2024-24559 (revision 2, source checked 26 Oct 2026, 13:27 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Low (CVSS 3.7)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: vyper 0.4.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- PyPI vyper: affected < 0.4.0; fixed in 0.4.0

## Suggested inspection (read-only)
- `python -m pip show vyper`: prints the installed version. Run with the environment that serves production active.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on vyper.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GHSA-6845-xw22-ffxv (OSV record GHSA-6845-xw22-ffxv lists affected ranges: PyPI vyper >=0 <0.4.0 (fixed))
- Verified: https://github.com/advisories/GHSA-6845-xw22-ffxv (GitHub-reviewed advisory GHSA-6845-xw22-ffxv lists affected ranges: PyPI vyper >=0 <0.4.0)

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