CVE-2026-39836
📛 CVE Title
Panic in Dial and LookupPort when handling NUL byte on Windows in net
Description
The Dial and LookupPort functions panic on Windows when provided with an input containing a NUL (0).
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-248: Uncaught Exception - Reserved
- 2026-04-07
- Published
- 2026-05-07 19:41 UTC
- Last updated
- 2026-05-08 21:30 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/39xxx/CVE-2026-39836.json
- Linked Threat
- CVE-2026-39836 — CVE-2026-39836
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
- 2026-05-07 20:16:43 UTC
- NVD last modified
- 2026-05-13 15:11:10 UTC
- NVD CVSS v3.1
- 7.5 / 10 HIGH source: nvd@nist.gov
- NVD CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H- Exploitability subscore
- 3.9 / 10
- Impact subscore
- 3.6 / 10
- EPSS score
- 0.0002 (probability of exploitation in next 30 days)
- EPSS percentile
- 5.71% vs all CVEs — higher = more likely to be exploited, as of 2026-05-24
NVD-assigned CWE(s):
CWE-476
(differs from the CNA list above)
NVD / KEV / EPSS data refreshed 2026-05-25 02:26 UTC. Re-run the 🛰 Backfill from NVD button above to refresh.
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-2026-28427 - Assigner
- Go
- Published
- May 7, 2026, 7:41:18 PM
- Updated
- May 8, 2026, 9:30:15 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
- 0.0200
- Vendors
- Go standard library
- Products
-
net (0 <1.25.10)net (1.26.0-0 <1.26.3)
ENISA description: The Dial and LookupPort functions panic on Windows when provided with an input containing a NUL (0).
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 2026-08-15 03:01 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
Affected products (1)
| Vendor | Product | Versions | Platforms |
|---|---|---|---|
| Go standard library | net |
0 (affected),
1.26.0-0 (affected)
|
— |
Affected products — CPE 2.3 (1) NVD
NVD's normalized CPE 2.3 matchers, used by vendor tools (vulnerability scanners, asset managers) for automated detection. Compare with the CNA's free-text "Affected products" section above.
cpe:2.3:a:golang:go:*:*:*:*:*:*:*:*
Vendor references (4)
References embedded in the original CVE record by the assigning CNA.
Web references (12)
DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.
- MSRC update guide: CVE-2026-39836 msrc
- https://attackerkb.com/topics/CVE-2026-39836 rapid7:attackerkb.com
- https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-28427 rapid7:euvd.enisa.europa.eu
- http://cwe.mitre.org/data/definitions/476.html rapid7:cwe.mitre.org
- https://security.alpinelinux.org/vuln/CVE-2026-39836 rapid7:security.alpinelinux.org
- https://groups.google.com/g/golang-announce/c/qcCIEXso47M tenable:groups.google.com
- https://go.dev/cl/775320 tenable:go.dev
- https://nvd.nist.gov/vuln/detail/CVE-2026-39836 tenable:nvd.nist.gov
- https://pkg.go.dev/vuln/GO-2026-4971 tenable:pkg.go.dev
- https://www.first.org/epss/ tenable:www.first.org
- https://www.cve.org/CVERecord?id=CVE-2026-39836 tenable:www.cve.org
- https://go.dev/issue/79006 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/775320 security@golang.org Patch
- https://go.dev/issue/79006 security@golang.org Issue Tracking
- https://groups.google.com/g/golang-announce/c/qcCIEXso47M security@golang.org Issue TrackingMailing List
- https://pkg.go.dev/vuln/GO-2026-4971 security@golang.org Vendor Advisory
Remediations (20)
Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.
-
web:cybersecuritynews.com
Microsoft released its March 2026 Patch Tuesday security update on March 10, 2026 , addressing 78 vulnerabilities across Windows, Microsoft Office, Azure, SQL Server, and .NET. The update includes one actively exploited zero-day vulnerability and multiple Critical-rated flaws demanding immediate attention from security teams. The most urgent fix this month is CVE - 2026 -21262, the sole zero-day ...
2026-05-23 21:51 UTC -
web:nvd.nist.gov
The NVD is the U.S. government repository of standards based vulnerability management data represented using the Security Content Automation Protocol (SCAP). This data enables automation of vulnerability management, security measurement, and compliance. The NVD includes databases of security checklist references, security-related software flaws, product names, and impact metrics. For ...
2026-05-23 21:51 UTC -
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.
2026-05-23 21:51 UTC -
web:sec.cloudapps.cisco.com
Multiple vulnerabilities in Cisco Identity Services Engine (ISE) could allow an authenticated, remote attacker to execute arbitrary commands on the underlying operating system of an affected device. To exploit these vulnerabilities, the attacker must have at least Read Only Admin credentials. These vulnerabilities are due to insufficient validation of user-supplied input. An attacker could ...
2026-05-23 21:51 UTC -
web:support.apple.com
This document describes the security content of iOS 26.2 and iPadOS 26.2.
2026-05-23 21:51 UTC -
web:www.cisecurity.org
<p>Multiple vulnerabilities have been discovered in Microsoft products, the most severe of which could allow for remote code execution. Successful exploitation of the most severe of these vulnerabilities could result in an attacker gaining the same privileges as the logged-on user. Depending on the privileges associated with the user, an attacker could then install programs; view, change, or ...
2026-05-23 21:51 UTC -
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.
2026-05-23 21:51 UTC -
web:www.penligent.ai
Second, chipset and OEM dependencies make remediation slower and messier than software-only patching. Google's bulletin explains the two Android patch levels for March 2026 and clarifies that devices with security patch levels of 2026 -03-01 or 2026 -03-05 are protected against the associated issues, depending on applicable components.
2026-05-23 21:51 UTC -
web:www.windowslatest.com
Windows 11 April 2026 update adds Narrator Copilot support, faster Settings, File Explorer fixes, and key security improvements.
2026-05-23 21:51 UTC -
web:zecurit.com
Get the complete breakdown of Microsoft's May 2026 Patch Tuesday. We analyze the latest security updates and all critical CVEs .
2026-05-23 21:51 UTC -
web:epatch.pa.gov
Why does PATCH exist? Its purpose is to better enable the public to obtain criminal history record checks. The repository was created and is maintained in accordance with Pennsylvania's Criminal History Information Act contained in Chapter 91 of Title 18, Crimes Code. This Act also directs the Pennsylvania State Police (PSP) to disseminate criminal history data to criminal justice agencies ...
2026-05-26 02:46 UTC -
web:forums.ea.com
Broken and Updated Sims 4 Mods and CC: patch 1.124, May 12 and 21, 2026 About This Thread This thread tracks Sims 4 mods and CC that have been "broken" or made obsolete by game update 1.124, May 12, 2026 , and the May 21 hotfix, or declared unsupported by their creators.
2026-05-26 02:46 UTC -
web:nvd.nist.gov
Official websites use .gov A .gov website belongs to an official government organization in the United States.
2026-05-26 02:46 UTC -
web:robertsspaceindustries.com
Hi Everyone! Time again for another Hotfix Central thread to keep you all up to date on things going on outside of the normal patch cycle in SC Alpha 4.8 LIVE! This will be a living document of...
2026-05-26 02:46 UTC -
web:support.microsoft.com
The Program Install and Uninstall troubleshooter helps you automatically repair issues when you're blocked from installing or removing programs.
2026-05-26 02:46 UTC -
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 02:46 UTC -
web:www.cve.org
At cve .org, we provide the authoritative reference method for publicly known information-security vulnerabilities and exposures
2026-05-26 02:46 UTC -
web:www.fixtrading.org
Learn more Standards and Guidelines FIX standards have driven electronic trading for 30 years and are constantly updated to support industry needs Learn more Events and Community Our member-driven global educational and networking events bring the industry together Learn more
2026-05-26 02:46 UTC -
web:www.oracle.com
Oracle Critical Patch Update Advisory - January 2026 Description A Critical Patch Update is a collection of patches for multiple security vulnerabilities. These patches address vulnerabilities in Oracle code and in third party components included in Oracle products. These patches are usually cumulative, but each advisory describes only the security patches added since the previous Critical ...
2026-05-26 02:46 UTC -
web:www.patchhawaii.org
PATCH provides access to registered and licensed child care, offers child care subsidies to eligible families, provides child development training and ECE scholarship opportunities, and assists those interested in starting a family child care business. PATCH is a free resource hub for families, child care professionals and communities of Hawaii.
2026-05-26 02:46 UTC
AI Forensic Analysis
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Raw JSON
The full cvelistV5 record. Download as CVE-2026-39836.json.
{
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"metrics": [
{
"cvssV3_1": {
"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",
"version": "3.1"
}
},
{
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{
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},
{
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"role": "CISA Coordinator",
"timestamp": "2026-05-08T16:36:25.079035Z",
"version": "2.0.3"
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"title": "CISA ADP Vulnrichment"
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"cna": {
"affected": [
{
"collectionURL": "https://pkg.go.dev",
"defaultStatus": "unaffected",
"packageName": "net",
"product": "net",
"programRoutines": [
{
"name": "Resolver.lookupPort"
},
{
"name": "Resolver.lookupAddr"
},
{
"name": "Resolver.lookupTXT"
},
{
"name": "Resolver.lookupNS"
},
{
"name": "Resolver.lookupMX"
},
{
"name": "Resolver.lookupSRV"
},
{
"name": "Dial"
},
{
"name": "DialTimeout"
},
{
"name": "Dialer.Dial"
},
{
"name": "Dialer.DialContext"
},
{
"name": "Listen"
},
{
"name": "ListenConfig.Listen"
},
{
"name": "ListenConfig.ListenPacket"
},
{
"name": "ListenPacket"
},
{
"name": "LookupAddr"
},
{
"name": "LookupCNAME"
},
{
"name": "LookupHost"
},
{
"name": "LookupIP"
},
{
"name": "LookupMX"
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{
"name": "LookupNS"
},
{
"name": "LookupPort"
},
{
"name": "LookupSRV"
},
{
"name": "LookupTXT"
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{
"name": "ResolveIPAddr"
},
{
"name": "ResolveTCPAddr"
},
{
"name": "ResolveUDPAddr"
},
{
"name": "Resolver.LookupAddr"
},
{
"name": "Resolver.LookupCNAME"
},
{
"name": "Resolver.LookupHost"
},
{
"name": "Resolver.LookupIP"
},
{
"name": "Resolver.LookupIPAddr"
},
{
"name": "Resolver.LookupMX"
},
{
"name": "Resolver.LookupNS"
},
{
"name": "Resolver.LookupNetIP"
},
{
"name": "Resolver.LookupPort"
},
{
"name": "Resolver.LookupSRV"
},
{
"name": "Resolver.LookupTXT"
}
],
"vendor": "Go standard library",
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{
"url": "https://groups.google.com/g/golang-announce/c/qcCIEXso47M"
},
{
"url": "https://go.dev/cl/775320"
},
{
"url": "https://pkg.go.dev/vuln/GO-2026-4971"
}
],
"title": "Panic in Dial and LookupPort when handling NUL byte on Windows in net"
}
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