CVE-2026-26958: Filippo.io/edwards25519 Filippo.io/edwards25519 MultiScalarMult Produces Invalid Results Vulnerability

LOW
Advisory Identifier: GHSA-fw7p-63qq-7hpr
Share
CWE-665
Published
Advisory Summary

CVE-2026-26958 is a LOW filippo.io/edwards25519 multiscalarmult produces invalid results vulnerability (CWE-665: Improper Initialization) affecting Filippo.io/edwards25519 libraries in the Go ecosystem. The issue involves filippo.io/edwards25519 multiscalarmult produces invalid results or undefined behavior if receiver is not the identity. Remediation is available by upgrading affected packages to version 1.1.1.

CVE-2026-26958 at a Glance

CVE Identifier CVE-2026-26958
GHSA Identifier GHSA-fw7p-63qq-7hpr
Severity LOW
CVSS v3.1 Base Score N/A
CWE Classification CWE-665: Improper Initialization
Affected Product Filippo.io/edwards25519
Package Ecosystem Go
Published Date
Last Updated

How to Fix CVE-2026-26958

To remediate this vulnerability, upgrade all affected Filippo.io/edwards25519 dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

filippo.io/edwards25519 fixed: 1.1.1 
Upgrade filippo.io/edwards25519 to 1.1.1
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

inspect dependencies for filippo.io/edwards25519

How to Check if You Are Affected

To determine whether your application is affected by CVE-2026-26958, inspect your project dependencies for Filippo.io/edwards25519:

inspect dependencies for filippo.io/edwards25519

Analyze the terminal output to locate any version of Filippo.io/edwards25519 in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.1.1), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-665: Improper Initialization, where the product does not initialize or incorrectly initializes a resource, which might leave the resource in an unexpected state when it is accessed or used. In Filippo.io/edwards25519, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

`(*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](https://go.dev/doc/tutorial/govulncheck).*

CVE-2026-26958 Affected Filippo.io/edwards25519 Versions

1 component(s)
Fixed Versions:
1.1.1
Product / Package Ecosystem Affected Versions Fixed Version
filippo.io/edwards25519
golang/filippo.io/edwards25519
Go
< 1.1.1
1.1.1

References

GitHub Advisory / Wiki ADVISORY
https://github.com/FiloSottile/edwards25519/security/advisories/GHSA-fw7p-63qq-7hpr
NVD — CVE-2026-26958 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-26958
Security Fix Commit FIX COMMIT
https://github.com/FiloSottile/edwards25519/commit/d1c650afb95fad0742b98d95f2eb2cf031393abb
Filippo.io/edwards25519 Source Repository REPOSITORY
https://github.com/FiloSottile/edwards25519
Filippo.io/edwards25519 Release RELEASE
https://github.com/FiloSottile/edwards25519/releases/tag/v1.1.1

Frequently Asked Questions

What is CVE-2026-26958?
CVE-2026-26958 is a security vulnerability in Filippo.io/edwards25519 involving filippo.io/edwards25519 MultiScalarMult produces invalid results or undefined behavior if receiver is not the identity under CWE-665: Improper Initialization.
Which Filippo.io/edwards25519 versions are affected?
Affected versions include releases prior to 1.1.1 across affected packages: filippo.io/edwards25519.
What version fixes CVE-2026-26958?
Upgrading to 1.1.1 (or the latest patched release for your respective branch) resolves the vulnerability.
Is filippo.io/edwards25519 affected?
Yes, filippo.io/edwards25519 is affected in releases prior to 1.1.1. Upgrade your dependency to 1.1.1 or later.
What CWE is associated with CVE-2026-26958?
CVE-2026-26958 is classified under CWE-665: Improper Initialization (The product does not initialize or incorrectly initializes a resource, which might leave the resource in an unexpected state when it is accessed or used.).
How can I check Go dependencies for CVE-2026-26958?
Run the dependency tree command: 'inspect dependencies for filippo.io/edwards25519'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-fw7p-63qq-7hpr",
  "modified" : "2026-02-20T16:46:42Z",
  "published" : "2026-02-18T22:37:15Z",
  "aliases" : [ "CVE-2026-26958" ],
  "summary" : "filippo.io/edwards25519 MultiScalarMult produces invalid results or undefined behavior if receiver is not the identity",
  "details" : "`(*Point).MultiScalarMult` failed to initialize its receiver.\n\nIf the method was called on an initialized point that is not the identity point, MultiScalarMult produced an incorrect result.\n\nIf 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.\n\n*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](https://go.dev/doc/tutorial/govulncheck).*",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "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"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "filippo.io/edwards25519"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "1.1.1"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/FiloSottile/edwards25519/security/advisories/GHSA-fw7p-63qq-7hpr"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-26958"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/FiloSottile/edwards25519/commit/d1c650afb95fad0742b98d95f2eb2cf031393abb"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/FiloSottile/edwards25519"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/FiloSottile/edwards25519/releases/tag/v1.1.1"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-665" ],
    "severity" : "LOW",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-02-18T22:37:15Z",
    "nvd_published_at" : "2026-02-19T23:16:26Z"
  }
}