CVE-2026-26958 | filippo.io/edwards25519 MultiScalarMult function produces invalid results or undefined behavior if receiver is not the identity

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.

Published: 2026-02-19 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-26958 is rated Low Risk (17/100): CVSS Low severity, with low exploitation likelihood (EPSS 0.37%). Mandatory action: Low composite risk—no urgent action required; patch on your normal maintenance cycle and revisit priority if CVSS or EPSS increases.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-26958

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.02% 0.37% +0.35%
2 2026-03-21 0.05% 0.02% -0.04%
3 2026-02-25 0.05%

Full EPSS history (4 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-26958

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
1.7 4.0 LOW
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/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network.
Attack complexity (AC:H)
Exploitation depends on constrained or hard-to-reproduce conditions.
Attack requirements (AT:P)
Additional preconditions must be present for exploitation.
Privileges required (PR:N)
No privileges are required.
User interaction (UI:N)
No user interaction is required.
Vulnerable system confidentiality impact (VC:N)
No confidentiality impact on the vulnerable system.
Vulnerable system integrity impact (VI:N)
No integrity impact on the vulnerable system.
Vulnerable system availability impact (VA:L)
Limited availability impact on the vulnerable system.
Subsequent system confidentiality impact (SC:N)
No confidentiality impact on subsequent systems.
Subsequent system integrity impact (SI:N)
No integrity impact on subsequent systems.
Subsequent system availability impact (SA:N)
No availability impact on subsequent systems.
Exploit maturity (threat) (E:U)
Unreported: no public PoC, no reported exploitation, and no known simplification tools.
Confidentiality requirement (CR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Integrity requirement (IR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Availability requirement (AR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Modified attack vector (MAV:X)
Not defined: scoring uses the Base Attack Vector (AV).
Modified attack complexity (MAC:X)
Not defined: scoring uses the Base Attack Complexity (AC).
Modified attack requirements (MAT:X)
Not defined: scoring uses the Base Attack Requirements (AT).
Modified privileges required (MPR:X)
Not defined: scoring uses the Base Privileges Required (PR).
Modified user interaction (MUI:X)
Not defined: scoring uses the Base User Interaction (UI).
Modified vulnerable system confidentiality impact (MVC:X)
Not defined: scoring uses the Base VC metric.
Modified vulnerable system integrity impact (MVI:X)
Not defined: scoring uses the Base VI metric.
Modified vulnerable system availability impact (MVA:X)
Not defined: scoring uses the Base VA metric.
Modified subsequent system confidentiality impact (MSC:X)
Not defined: scoring uses the Base SC metric.
Modified subsequent system integrity impact (MSI:X)
Not defined: scoring uses the Base SI metric.
Modified subsequent system availability impact (MSA:X)
Not defined: scoring uses the Base SA metric.
Safety (supplemental) (S:X)
Not evaluated.
Automatable (supplemental) (AU:X)
Not evaluated.
Recovery (supplemental) (R:X)
Not evaluated.
Value density (supplemental) (V:X)
Not evaluated.
Vulnerability response effort (supplemental) (RE:X)
Not evaluated.
Provider urgency (supplemental) (U:X)
Not evaluated.
[email protected]

Weakness enumeration for CVE-2026-26958

GitHub Security Advisory for CVE-2026-26958

GHSA-fw7p-63qq-7hpr · Severity: low · Ecosystem: go — filippo.io/edwards25519 MultiScalarMult produces invalid results or undefined behavior if receiver is not the identity

OS Trackers for CVE-2026-26958

vendor priority summary link
debian not yet assigned CVE-2026-26958 not yet assigned priority: Debian including 1 source packages (golang-filippo-edwards25519), 4 status rows across 4 suites (bookworm, forky, sid, trixie): open 2, resolved 2. https://security-tracker.debian.org/tracker/CVE-2026-26958
redhat low https://access.redhat.com/security/cve/CVE-2026-26958
suse medium CVE-2026-26958 severity moderate: SUSE including 22 source package names (cosign-3.0.5-1.1, cosign-3.0.5-150400.3.35.1, …), 62 product×package rows across 40 product lines (Image SL-Micro, Image SL-Micro-Azure, … (40 product lines)): Fixed 46, First Fixed 16. https://www.suse.com/security/cve/CVE-2026-26958/
ubuntu medium CVE-2026-26958 medium priority: Ubuntu including 1 source packages (golang-filippo-edwards25519), 4 status rows across 4 suites (jammy, noble, questing, upstream): needs-triage 4. https://ubuntu.com/security/CVE-2026-26958

Affected software / configurations for CVE-2026-26958

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2026-26958

cvelogic Threat Intelligence