Vulnerability · Published Feb 19, 2026 · Assigned by GitHub_M
CVE-2026-26958filippo.io/edwards25519 MultiScalarMult function produces invalid results or undefined behavior if receiver is not the identity
Low 1.7
In plain English
A low-severity security flaw in filippo.io/edwards25519 from FiloSottile. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 36% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
filippo.io/edwards25519 is a Go library implementing the edwards25519 elliptic curve with APIs for building cryptographic primitives. In versions 1.1.0 and earlier, MultiScalarMult produces invalid results or undefined behavior if the receiver is not the identity point. If (*Point).MultiScalarMult is called on an initialized point that is not the identity point, it returns an incorrect result. If the method is called on an uninitialized point, the behavior is undefined. In particular, if the receiver is the zero value, MultiScalarMult returns an invalid point that compares Equal to every other point. Note that MultiScalarMult is a rarely used, advanced API. For example, users who depend on filippo.io/edwards25519 only through github.com/go-sql-driver/mysql are not affected. This issue has been fixed in version 1.1.1.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | golang-filippo-edwards25519 | no fix listed | DEBIAN-CVE-2026-26958 |
| Debian:13 | golang-filippo-edwards25519 | no fix listed | DEBIAN-CVE-2026-26958 |
| Debian:14 | golang-filippo-edwards25519 | 1.2.0-1 | DEBIAN-CVE-2026-26958 |
| Go | filippo.io/edwards25519 | 1.1.1 | GHSA-fw7p-63qq-7hpr |
| Go | filippo.io/edwards25519 | 1.1.1 | GO-2026-4503 |
| Ubuntu:22.04:LTS | golang-filippo-edwards25519 | no fix listed | UBUNTU-CVE-2026-26958 |
| Ubuntu:24.04:LTS | golang-filippo-edwards25519 | no fix listed | UBUNTU-CVE-2026-26958 |
| Ubuntu:25.10 | golang-filippo-edwards25519 | no fix listed | UBUNTU-CVE-2026-26958 |
| Ubuntu:26.04:LTS | golang-filippo-edwards25519 | no fix listed | UBUNTU-CVE-2026-26958 |
| Ubuntu:26.10 | golang-filippo-edwards25519 | no fix listed | UBUNTU-CVE-2026-26958 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| FiloSottile | filippo.io/edwards25519 | < 1.1.1 |
Weakness: CWE-665 · Vector: 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