CVE-2026-39829

Description

The RSA and DSA public key parsers did not enforce size limits on key parameters. A crafted public key with an excessively large modulus or DSA parameter could cause several minutes of CPU consumption during signature verification. This could be triggered by unauthenticated clients during public key authentication. RSA moduli are now limited to 8192 bits, and DSA parameters are validated per FIPS 186-2.

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: 7.5 / 10 HIGH MS rating: Important
CWE(s): CWE-1176: Inefficient CPU Computation
Reserved: 2026-04-07
Published: 2026-05-22 02:31 UTC
Last updated: 2026-05-22 18:53 UTC
Source: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/39xxx/CVE-2026-39829.json
Linked Threat: CVE-2026-39829 — CVE-2026-39829

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: 0.0007 (probability of exploitation in next 30 days)
EPSS percentile: 22.28% 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-2026-31396
Assigner: Go
Published: May 22, 2026, 2:31:27 AM
Updated: May 22, 2026, 6:53:33 PM
EUVD base score (CVSS 3.1): 7.5 / 10
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EUVD-reported EPSS: 0.0900
Vendors: golang.org/x/crypto
Products: golang.org/x/crypto/ssh (0 <0.52.0)

ENISA description: The RSA and DSA public key parsers did not enforce size limits on key parameters. A crafted public key with an excessively large modulus or DSA parameter could cause several minutes of CPU consumption during signature verification. This could be triggered by unauthenticated clients during public key authentication. RSA moduli are now limited to 8192 bits, and DSA parameters are validated per FIPS 186-2.

EUVD references (5)

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: Important
MS CVSS base score: 7.5 / 10 (temporal 7.5)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
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 (5)

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

Web references (10)

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-2026-39829 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/79565 tenable:go.dev
https://go.dev/cl/781661 tenable:go.dev
https://nvd.nist.gov/vuln/detail/CVE-2026-39829 tenable:nvd.nist.gov
https://pkg.go.dev/vuln/GO-2026-5018 tenable:pkg.go.dev
https://www.cve.org/CVERecord?id=CVE-2026-39829 tenable:www.cve.org
https://go.dev/cl/781641 tenable:go.dev

NVD-tagged references (5)

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/781641 security@golang.org
https://go.dev/cl/781661 security@golang.org
https://go.dev/issue/79565 security@golang.org
https://groups.google.com/g/golang-announce/c/a082jnz-LvI security@golang.org
https://pkg.go.dev/vuln/GO-2026-5018 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 Vault - CVE Database & Security Research Hub

web:cvevault.com

CVE Vault - Search and explore Common Vulnerabilities and Exposures ( CVE ) database. Find security vulnerabilities by CVE ID, vendor, severity, and year. Stay secure with comprehensive CVE information.

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
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
Public Key Parser Vulnerability in Go by Google CVE-2026-39829

web:securityvulnerability.io

Learn about the vulnerability in Go's public key parsers that can lead to CPU exhaustion during signature verification. CVE-2026-39829 .

2026-05-26 03:00 UTC
Known Exploited Vulnerabilities Catalog - CISA

web:www.cisa.gov

For the benefit of the cybersecurity community and network defenders—and to help every organization better manage vulnerabilities and keep pace with threat activity—CISA maintains the authoritative source of vulnerabilities that have been exploited in the wild. Organizations should use the KEV catalog as an input to their vulnerability management prioritization framework.

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

web:www.crowdstrike.com

Microsoft has released security updates for 130 vulnerabilities, including 30 critical, in its May 2026 Patch Tuesday rollout.

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-2026-39829 - Info Vulnerability - TheHackerWire

web:www.thehackerwire.com

CVE-2026-39829 is a Info severity vulnerability (CVSS 0). The RSA and DSA public key parsers did not enforce size limits on key parameters. A crafted public key with...

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-2026-39829.json.

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              "attackComplexity": "LOW",
              "attackVector": "NETWORK",
              "availabilityImpact": "HIGH",
              "baseScore": 7.5,
              "baseSeverity": "HIGH",
              "confidentialityImpact": "NONE",
              "integrityImpact": "NONE",
              "privilegesRequired": "NONE",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
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                "timestamp": "2026-05-22T18:52:38.155082Z",
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            },
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        },
        {
          "url": "https://pkg.go.dev/vuln/GO-2026-5018"
        }
      ],
      "title": "Invoking  pathological RSA/DSA parameters may cause DoS in golang.org/x/crypto/ssh"
    }
  },
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    "dateReserved": "2026-04-07T18:13:03.528Z",
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