filippo.io/edwards25519 MultiScalarMult produces invalid results or undefined behavior if receiver is not the identity

Exploitation

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

CVSS 4.0

1.7 · CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U · score source

EPSS

• CVE-2026-26958: 0.41% estimated exploitation activity in the next 30 days; percentile 35.87 (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.

(Point).MultiScalarMult failed to initialize its receiver. If the method was called on an initialized point that is not the identity point, MultiScalarMult produced an incorrect result. If the method was called on an uninitialized point, the behavior was undefined. In particular, if the receiver was the zero value, MultiScalarMult returned an invalid point that compared Equal to every point. Note that MultiScalarMult is a rarely used advanced API. For example, if you only depend on filippo.io/edwards25519 via github.com/go-sql-driver/mysql, you are not affected. If you were notified of this issue despite not being affected, consider switching to a vulnerability scanner that is more precise and respectful of your attention, like govulncheck.

Published by the source

18 Feb 2026, 22:37 UTC

Last modified by the source

21 Feb 2026, 09:56 UTC

Source last checked

26 Oct 2026, 15:14 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-fw7p-63qq-7hpr

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# Patch Next advisory brief: CVE-2026-26958

Advisory: filippo.io/edwards25519 MultiScalarMult produces invalid results or undefined behavior if receiver is not the identity
IDs: CVE-2026-26958, GHSA-fw7p-63qq-7hpr
Record: https://patchnext.com/advisories/cve-2026-26958 (revision 1, source checked 26 Oct 2026, 15:14 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Low (CVSS 1.7)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: filippo.io/edwards25519 1.1.1. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go filippo.io/edwards25519: affected < 1.1.1; fixed in 1.1.1

## Suggested inspection (read-only)
- Go filippo.io/edwards25519: 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 filippo.io/edwards25519.
- 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-fw7p-63qq-7hpr (GitHub-reviewed advisory GHSA-fw7p-63qq-7hpr lists affected ranges: Go filippo.io/edwards25519 >=0 <1.1.1)

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