CVE-2026-33814

Description

When processing HTTP/2 SETTINGS frames, transport will enter an infinite loop of writing CONTINUATION frames if it receives a SETTINGS_MAX_FRAME_SIZE with a value of 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-835: Loop with Unreachable Exit Condition ('Infinite Loop')
Reserved: 2026-03-23
Published: 2026-05-07 19:41 UTC
Last updated: 2026-05-08 18:01 UTC
Source: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/33xxx/CVE-2026-33814.json
Linked Threat: CVE-2026-33814 — CVE-2026-33814

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 20:16:42 UTC
NVD last modified: 2026-05-13 14:41:59 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: 5.07% vs all CVEs — higher = more likely to be exploited, as of 2026-05-24

NVD-assigned CWE(s): CWE-835 (differs from the CNA list above)

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-2026-28420
Assigner: Go
Published: May 7, 2026, 7:41:17 PM
Updated: May 8, 2026, 6:01:02 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, golang.org/x/net
Products: net/http (1.26.0-0 <1.26.3)

golang.org/x/net/http2 (0 <0.53.0)

net/http (0 <1.25.10)

ENISA description: When processing HTTP/2 SETTINGS frames, transport will enter an infinite loop of writing CONTINUATION frames if it receives a SETTINGS_MAX_FRAME_SIZE with a value of 0.

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 2026-08-12 01:09 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 1.26.3-1)
https://learn.microsoft.com/en-us/azure/azure-linux/tutorial-azure-linux-upgrade — None Available / CBL-Mariner Releases

Affected products (2)

Vendor	Product	Versions	Platforms
golang.org/x/net	golang.org/x/net/http2	`0` (affected)	—
Go standard library	net/http	`0` (affected), `1.26.0-0` (affected)	—

Affected products — CPE 2.3 (2) 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:*:*:*:*:*:*:*:*
cpe:2.3:a:golang:http2:*:*:*:*:*:go:*:*

Vendor references (5)

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

Web references (14)

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-2026-33814 msrc
None Available msrc
https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-28420 rapid7:euvd.enisa.europa.eu
http://cwe.mitre.org/data/definitions/835.html rapid7:cwe.mitre.org
https://attackerkb.com/topics/CVE-2026-33814 rapid7:attackerkb.com
https://security.alpinelinux.org/vuln/CVE-2026-33814 rapid7:security.alpinelinux.org
https://groups.google.com/g/golang-announce/c/qcCIEXso47M tenable:groups.google.com
https://go.dev/cl/761640 tenable:go.dev
https://go.dev/cl/761581 tenable:go.dev
https://nvd.nist.gov/vuln/detail/CVE-2026-33814 tenable:nvd.nist.gov
https://pkg.go.dev/vuln/GO-2026-4918 tenable:pkg.go.dev
https://www.first.org/epss/ tenable:www.first.org
https://www.cve.org/CVERecord?id=CVE-2026-33814 tenable:www.cve.org
https://go.dev/issue/78476 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/761581 security@golang.org Patch
https://go.dev/cl/761640 security@golang.org Patch
https://go.dev/issue/78476 security@golang.org Issue TrackingMailing List
https://groups.google.com/g/golang-announce/c/qcCIEXso47M security@golang.org Release Notes
https://pkg.go.dev/vuln/GO-2026-4918 security@golang.org Vendor Advisory

Remediations (11)

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

Microsoft and Adobe Patch Tuesday, April 2026 Security Update Review

web:blog.qualys.com

With Qualys Policy Audit's out-of-the-box mitigation or Compensatory Controls, which reduce the risk of a vulnerability being exploited because the remediation ( fix / patch ) cannot be done immediately, these security controls are not recommended by any industry standards, such as CIS and DISA-STIG.

2026-05-23 21:48 UTC
Microsoft Patch Tuesday April 2026 - 168 Vulnerabilities Fixed ...

web:cybersecuritynews.com

Microsoft has released its April 2026 Patch Tuesday security update, addressing 168 vulnerabilities across its product portfolio including one actively exploited zero-day and one publicly disclosed flaw that organizations must prioritize immediately.

2026-05-23 21:48 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?

2026-05-23 21:48 UTC
Security Update Guide - Microsoft Security Response Center

web:msrc.microsoft.com

Security Update Guide - Microsoft Security Response Center

2026-05-23 21:48 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.

2026-05-23 21:48 UTC
Critical Patches Issued for Microsoft Products, April 14, 2026

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 21:48 UTC
April 2026 Patch Tuesday: Updates and Analysis | CrowdStrike

web:www.crowdstrike.com

Microsoft's April 2026 Patch Tuesday addresses 164 CVEs , featuring 8 Critical vulnerabilities, one exploited zero-day, and one disclosed zero-day.

2026-05-23 21:48 UTC
Microsoft Patch Tuesday - April 2026 - Lansweeper

web:www.lansweeper.com

The April 2026 edition of Patch Tuesday brings us 171 fixes, with 8 rated as critical. We've listed the most important changes below. Microsoft SharePoint Server Spoofing Vulnerability CVE - 2026 -32201 is the only actively exploited vulnerability in this month's release.

2026-05-23 21:48 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.

2026-05-23 21:48 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 .

2026-05-23 21:48 UTC
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 02:46 UTC

AI Forensic Analysis

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Raw JSON

The full cvelistV5 record. Download as CVE-2026-33814.json.

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              "confidentialityImpact": "NONE",
              "integrityImpact": "NONE",
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      "title": "Infinite loop in HTTP/2 transport when given bad SETTINGS_MAX_FRAME_SIZE in net/http/internal/http2 in golang.org/x/net"
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