CVE-2026-39828

Description

When an SSH server authentication callback returned PartialSuccessError with non-nil Permissions, those permissions were silently discarded, potentially dropping certificate restrictions such as force-command after a second factor succeeded. Returning non-nil Permissions with PartialSuccessError now results in a connection error.

Overview

State: PUBLISHED
Assigner (CNA): Go
CVSS severity: high
CVSS score: 8.8 / 10
CVSS vector: AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Effective score: 8.8 / 10 HIGH source: CNA overview
MSRC score: 6.3 / 10 MEDIUM MS rating: Moderate
CWE(s): CWE-863: Incorrect Authorization
Reserved: 2026-04-07
Published: 2026-05-22 02:31 UTC
Last updated: 2026-05-22 17:44 UTC
Source: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/39xxx/CVE-2026-39828.json
Linked Threat: CVE-2026-39828 — CVE-2026-39828

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 04:16:22 UTC
NVD last modified: 2026-05-22 04:16:22 UTC
EPSS score: 0.0003 (probability of exploitation in next 30 days)
EPSS percentile: 8.85% 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-2026-31394
Assigner: Go
Published: May 22, 2026, 2:31:26 AM
Updated: May 22, 2026, 5:44:19 PM
EUVD base score (CVSS 3.1): 6.3 / 10
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
EUVD-reported EPSS: 0.0300
Vendors: golang.org/x/crypto
Products: golang.org/x/crypto/ssh (0 <0.52.0)

ENISA description: When an SSH server authentication callback returned PartialSuccessError with non-nil Permissions, those permissions were silently discarded, potentially dropping certificate restrictions such as force-command after a second factor succeeded. Returning non-nil Permissions with PartialSuccessError now results in a connection error.

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: 6.3 / 10 (temporal 5.8)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L/E:U
Release: 2026-May

Microsoft remediations / KB articles (2)

CBL-Mariner Releases — Vendor Fix / Security Update (fixed build 1.12.15-8)
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	`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-2026-39828 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/79562 tenable:go.dev
https://nvd.nist.gov/vuln/detail/CVE-2026-39828 tenable:nvd.nist.gov
https://pkg.go.dev/vuln/GO-2026-5014 tenable:pkg.go.dev
https://www.cve.org/CVERecord?id=CVE-2026-39828 tenable:www.cve.org
https://go.dev/cl/781621 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/781621 security@golang.org
https://go.dev/issue/79562 security@golang.org
https://groups.google.com/g/golang-announce/c/a082jnz-LvI security@golang.org
https://pkg.go.dev/vuln/GO-2026-5014 security@golang.org

Remediations (10)

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

Security Advisory Bulletin 064 | Ubiquiti Community

web:community.ui.com

Published: May 21, 2026 Updated: May 22, 2026 Version: 1.1 Revision: 1.1 Summary 1 of 5 A malicious actor with access to the network and high privileges could exploit an Improper Input Validation vulnerability found in UniFi OS devices to execute a Command Injection. Affected Products: UniFi OS Server (Version 5.0.6 and earlier) Mitigation : Update your UniFi OS Server to Version 5.0.8 or later ...

2026-05-26 03:00 UTC
CVE‑2026‑42898: Remote Code Execution in Microsoft Dynamics 365 On ...

web:integsec.com

A technical appendix below provides detection, remediation , and best‑practice guidance for your security and IT teams. S1 — Background & History CVE‑2026‑42898 was publicly disclosed on May 12, 2026 , and is assigned to an improper control of code generation in Microsoft Dynamics 365 on‑premises.

2026-05-26 03:00 UTC
Patch Tuesday, April 2026 Edition - Krebs on Security

web:krebsonsecurity.com

For a clickable, per- patch breakdown, check out the SANS Internet Storm Center Patch Tuesday roundup. Running into problems applying any of these updates?

2026-05-26 03:00 UTC
Security Update Guide - Microsoft

web:portal.msrc.microsoft.com

The Security Update Guide provides information on the latest Microsoft security updates, helping users understand and address potential vulnerabilities effectively.

2026-05-26 03:00 UTC
CVE-2026-42897 Exchange OWA Mitigation M2: What Admins Must Verify

web:windowsforum.com

Microsoft's Fastest Fix Is a Mitigation , Not a Patch The important detail in Microsoft's May 14 notice is that there is no permanent Exchange security update available yet for CVE - 2026 -42897. Microsoft says it is working on one and will release it later for affected supported paths, but today's defensive action is mitigation .

2026-05-26 03:00 UTC
Microsoft April 2026 Patch Tuesday fixes 167 flaws, 2 zero-days

web:www.bleepingcomputer.com

Today is Microsoft's April 2026 Patch Tuesday with security updates for 167 flaws, including 2 zero-day vulnerabilities.

2026-05-26 03:00 UTC
March 2026 Patch Tuesday: Updates and Analysis | CrowdStrike

web:www.crowdstrike.com

Microsoft's March 2026 Patch Tuesday addresses 82 CVEs , featuring eight Critical vulnerabilities.

2026-05-26 03:00 UTC
Oracle Critical Patch Update Advisory - April 2026

web:www.oracle.com

This Critical Patch Update contains 481 new security patches across the product families listed below. Please note that an MOS note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at April 2026 Critical Patch Update: Executive Summary and Analysis.

2026-05-26 03:00 UTC
CVE-2026-39828: privilege escalation vulnerability in crypto (Go)

web:www.resolvedsecurity.com

What is CVE-2026-39828 About? This vulnerability allows for privilege escalation by silently discarding essential certificate restrictions linked to `PartialSuccessError` in SSH server authentication callbacks.

2026-05-26 03:00 UTC
Patch Tuesday May 2026: Security Updates & CVE Analysis

web:zecurit.com

Get the complete breakdown of Microsoft's May 2026 Patch Tuesday. We analyze the latest security updates and all critical CVEs .

2026-05-26 03:00 UTC

AI Forensic Analysis

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Raw JSON

The full cvelistV5 record. Download as CVE-2026-39828.json.

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              "confidentialityImpact": "LOW",
              "integrityImpact": "LOW",
              "privilegesRequired": "LOW",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L",
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