CVE-2026-46598

Description

For certain crafted inputs, a 'ed25519.PrivateKey' was created by casting malformed wire bytes, leading to a panic when used.

Overview

State: PUBLISHED
Assigner (CNA): Go
CVSS severity: high
CVSS score: 7.5 / 10
CVSS vector: AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Effective score: 7.5 / 10 HIGH source: CNA overview
MSRC score: 5.3 / 10 MEDIUM MS rating: Moderate
CWE(s): CWE-129: Improper Validation of Array Index
Reserved: 2026-05-15
Published: 2026-05-22 02:31 UTC
Last updated: 2026-05-22 18:14 UTC
Source: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/46xxx/CVE-2026-46598.json
Linked Threat: CVE-2026-46598 — CVE-2026-46598

NVD triage scoring NVD CVE 2.0

Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.

NVD published: 2026-05-22 04:16:26 UTC
NVD last modified: 2026-05-22 04:16:26 UTC
EPSS score: 0.0004 (probability of exploitation in next 30 days)
EPSS percentile: 11.86% vs all CVEs — higher = more likely to be exploited, as of 2026-05-24

European Union Vulnerability Database ENISA EUVD

ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.

EUVD ID: EUVD-2026-31402
Assigner: Go
Published: May 22, 2026, 2:31:27 AM
Updated: May 22, 2026, 6:14:37 PM
EUVD base score (CVSS 3.1): 5.3 / 10
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
EUVD-reported EPSS: 0.0500
Vendors: golang.org/x/crypto
Products: golang.org/x/crypto/ssh/agent (0 <0.52.0)

ENISA description: For certain crafted inputs, a 'ed25519.PrivateKey' was created by casting malformed wire bytes, leading to a panic when used.

EUVD references (4)

Microsoft Security Response Center MSRC

Microsoft's vendor-authoritative record from the Security Update Guide — its own CVSS score, impact, severity rating, exploit assessment, and KB-article fixes. Refreshed 2026-07-28 03:00 UTC (source: CVRF).

MS severity: Moderate
MS CVSS base score: 5.3 / 10 (temporal 4.9)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/E:U
Release: 2026-May

Microsoft remediations / KB articles (2)

CBL-Mariner Releases — Vendor Fix / Security Update (fixed build 1.9.5-14)
https://learn.microsoft.com/en-us/azure/azure-linux/tutorial-azure-linux-upgrade — None Available / CBL-Mariner Releases

Affected products (1)

Vendor	Product	Versions	Platforms
golang.org/x/crypto	golang.org/x/crypto/ssh/agent	`0` (affected)	—

Vendor references (4)

References embedded in the original CVE record by the assigning CNA.

Web references (9)

DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.

None Available msrc
MSRC update guide: CVE-2026-46598 msrc
https://www.first.org/epss/ tenable:www.first.org
https://groups.google.com/g/golang-announce/c/a082jnz-LvI tenable:groups.google.com
https://go.dev/issue/79596 tenable:go.dev
https://nvd.nist.gov/vuln/detail/CVE-2026-46598 tenable:nvd.nist.gov
https://pkg.go.dev/vuln/GO-2026-5033 tenable:pkg.go.dev
https://www.cve.org/CVERecord?id=CVE-2026-46598 tenable:www.cve.org
https://go.dev/cl/781360 tenable:go.dev

NVD-tagged references (4)

Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.

https://go.dev/cl/781360 security@golang.org
https://go.dev/issue/79596 security@golang.org
https://groups.google.com/g/golang-announce/c/a082jnz-LvI security@golang.org
https://pkg.go.dev/vuln/GO-2026-5033 security@golang.org

Remediations (10)

Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.

Microsoft Defender CVE-2026-41091 and CVE-2026-45498 Exploited

web:blog.gridinsoft.com

Microsoft has confirmed exploitation of two Microsoft Defender vulnerabilities fixed in the May 2026 security update cycle. CVE - 2026 -41091 is an elevation-of-privilege flaw in the Microsoft Malware Protection Engine, while CVE - 2026 -45498 is a denial-of-service flaw in the Microsoft Defender Antimalware Platform . The first bug matters more for incident response because a local authorized ...

2026-05-26 03:00 UTC
CISA Warns of Exploited Microsoft Defender 0-Day Flaws

web:cyberpress.org

The U.S. Cybersecurity and Infrastructure Security Agency (CISA) has added two actively exploited Microsoft Defender vulnerabilities to its Known Exploited Vulnerabilities (KEV) catalog, issuing an urgent remediation directive for federal agencies with a due date of June 3, 2026 .

2026-05-26 03:00 UTC
Microsoft Defender Flaws CVE-2026-41091 And -45498

web:cybersecurefox.com

Given the confirmed active exploitation and the CISA deadline of June 3, 2026 , remediation of CVE - 2026 -41091 should be treated as critical —immediate verification and updating of all systems with active Microsoft Defender, with special attention to servers and workstations that have access to sensitive data or privileged accounts.

2026-05-26 03:00 UTC
Microsoft Defender CVE-2026-41091 and CVE-2026-45498 Exploited

web:howtofix.guide

CISA added both CVE - 2026 -41091 and CVE - 2026 -45498 to its Known Exploited Vulnerabilities catalog on May 20, with a federal remediation due date of June 3, 2026 . [4] That KEV entry does not mean every home PC is currently targeted, but it is a clear signal that defenders should not wait for the next normal maintenance window.

2026-05-26 03:00 UTC
Microsoft Issues Second Biggest Patch Tuesday Ever in April

web:redmondmag.com

Microsoft April 2026 Patch Tuesday fixed 163 CVEs , marking its second-largest security update. Three zero-day vulnerabilities impacted SharePoint, Chromium-based Edge workflows and Microsoft Defender.

2026-05-26 03:00 UTC
Microsoft Defender CVE-2026-41091 & CVE-2026-45498

web:thecyberexpress.com

Microsoft confirms active exploitation of CVE - 2026 -41091 and CVE - 2026 -45498 in Defender, with CVSS-rated risks, KEV listing, and urgent patches issued.

2026-05-26 03:00 UTC
Microsoft Patches Two Actively Exploited Defender Zero-Days on Windows

web:windowsreport.com

Microsoft patched two actively exploited Defender zero-days affecting Windows systems and security components.

2026-05-26 03:00 UTC
Critical Microsoft Defender Vulnerabilities: How to Patch CVE-2026 ...

web:www.archynewsy.com

Understanding the Exploited Vulnerabilities The security risks involve two distinct CVE -tracked flaws that Microsoft has addressed in its latest updates: Critical Microsoft Defender Vulnerabilities Antimalware Platform CVE - 2026 -41091 (CVSS Score: 7.8): This vulnerability involves improper link resolution before file access, commonly known as "link following." By successfully exploiting ...

2026-05-26 03:00 UTC
Microsoft Defender vulnerabilities exploited in the wild (CVE-2026 ...

web:www.helpnetsecurity.com

Attackers are actively exploiting two Microsoft Defender vulnerabilities ( CVE - 2026 -41091 and CVE - 2026 -45498), Microsoft acknowledged.

2026-05-26 03:00 UTC
Microsoft Technical Security Notifications

web:www.microsoft.com

Security Update Guide Notifications Microsoft's free Security Update Guide Notifications provide links to security-related software updates and notification of re-released security updates. These notifications are sent via email throughout the month as needed.

2026-05-26 03:00 UTC

AI Forensic Analysis

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Raw JSON

The full cvelistV5 record. Download as CVE-2026-46598.json.

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              "privilegesRequired": "NONE",
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