soroban-fixed-point-math has Incorrect Rounding and Overflow Handling in Signed Fixed-Point Math with Negatives

Exploitation

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

CVSS

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

EPSS

• CVE-2026-24783: 0.41% estimated exploitation activity in the next 30 days; percentile 35.13 (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.

Impact Incorrect rounding direction for signed mul and div operations The mulDiv(x, y, z) function incorrectly handled cases where both the intermediate product $x y$ and the divisor $z$ were negative. The logic assumed that if the intermediate product was negative, the final result must also be negative, neglecting the sign of $z$. This resulted in rounding being applied in the wrong direction for cases where both $x y$ and $z$ were negative. The functions most at risk are fixeddivfloor and fixeddivceil, as they often use non-constant numbers as the divisor $z$ in mulDiv. This error is present in all signed FixedPoint and SorobanFixedPoint implementations, including i64, i128, and I256. Negative Overflow in i64 The mulDiv(x, y, z) function for i64 used the i128 type to handle "phantom overflows". These are overflows that occur intermediately during a calculation, like when computing the intermediate product $x y$. When the final result of mulDiv was computed in i128, it was scaled…

Published by the source

28 Jan 2026, 16:18 UTC

Last modified by the source

28 Jan 2026, 16:18 UTC

Source last checked

26 Oct 2026, 15:39 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-x5m4-43jf-hh65

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# Patch Next advisory brief: CVE-2026-24783

Advisory: soroban-fixed-point-math has Incorrect Rounding and Overflow Handling in Signed Fixed-Point Math with Negatives
IDs: CVE-2026-24783, GHSA-x5m4-43jf-hh65
Record: https://patchnext.com/advisories/cve-2026-24783 (revision 1, source checked 26 Oct 2026, 15:39 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: soroban-fixed-point-math 1.4.1, 1.3.1. A vendor fix does not mean a deployment is fixed.

## Affected components
- crates.io soroban-fixed-point-math: affected >= 1.4.0, <= 1.4.0; >= 1.3.0, <= 1.3.0; fixed in 1.4.1, 1.3.1

## Suggested inspection (read-only)
- crates.io soroban-fixed-point-math: check the installed version with your package manager.

## 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 soroban-fixed-point-math.
- 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://github.com/advisories/GHSA-x5m4-43jf-hh65 (GitHub-reviewed advisory GHSA-x5m4-43jf-hh65 lists affected ranges: crates.io soroban-fixed-point-math >=1.4.0 =1.3.0 <=1.3.0)

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