Your RSA-2048 keys break in 2030. Find every one of them before attackers do.
🐹 Go

CVE-2026-26958

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

Also known asGHSA-fw7p-63qq-7hprGO-2026-4503
Published
Feb 19, 2026
Updated
Jun 18, 2026
Affected
1 pkg
Patched
1 / 1
Exploits
None indexed

EPSS Exploitation Probability

via FIRST.org ↗
0.4%probability of exploitation in next 30 days
Lower Risk28th percentile+0.35%
0.00%0.29%0.58%0.87%0.1%0.0%0.0%0.0%0.4%Mar 26May 26Jun 26

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Blast Radius

1 pkg affected
🐹filippo.io/edwards25519

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.

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

1 total 1 fixed
EcosystemPackageVulnerable rangeFix
🐹Gofilippo.io/edwards25519all versions1.1.1

Detection & mitigation playbook

Open-source dependency
  1. Detect

    Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for filippo.io/edwards25519. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

  2. Fix

    Update filippo.io/edwards25519 to 1.1.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-26958 is resolved across your whole dependency graph.

  3. Workarounds

    If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

  4. How O3 protects you

    O3 pinpoints whether CVE-2026-26958 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to CVE-2026-26958. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

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
O3 Security · Impact-Aware SCA

Is CVE-2026-26958 in your dependencies?

O3 detects CVE-2026-26958 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.