CVE-2026-77791

Description

Uncontrolled Resource Consumption vulnerability in Apache Tomcat during sending of WebSocket close message enabled a DoS attack. This issue affects Apache Tomcat: from 11.0.0-M5 through 11.0.25, from 10.1.8 through 10.1.59, from 9.0.74 through 9.0.121. The following versions were EOL at the time the CVE was created but are known to be affected: from 8.5.88 through 8.5.100. Other unsupported versions may also be affected. Users are recommended to upgrade to version 11.0.26, 10.1.60 or 9.0.122, which fix the issue.

Overview

State: PUBLISHED
Assigner (CNA): apache
CVSS severity: —
CVSS score: —
CVSS vector: —
Effective score: 7.5 / 10 HIGH source: NVD
CWE(s): CWE-400
Reserved: 2026-08-21
Published: 2026-09-23 11:20 UTC
Last updated: 2026-09-23 18:10 UTC
Source: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/77xxx/CVE-2026-77791.json

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: 2026-09-23 12:17:06 UTC
NVD last modified: 2026-09-23 19:19:19 UTC
NVD CVSS v3.1: 7.5 / 10 HIGH source: 134c704f-9b21-4f2e-91b3-4a467353bcc0
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

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-2026-85229
Assigner: apache
Published: Sep 23, 2026, 11:20:50 AM
Updated: Sep 23, 2026, 6:10:44 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: 0.0000
Vendors: Apache Software Foundation
Products: Apache Tomcat (10.1.8 ≤10.1.59)

Apache Tomcat (9.0.74 ≤9.0.121)

Apache Tomcat (11.0.0-M5 ≤11.0.25)

Apache Tomcat (8.5.88 ≤8.5.100)
Aliases: GHSA-9cg7-2q68-g3mq

ENISA description: Uncontrolled Resource Consumption vulnerability in Apache Tomcat during sending of WebSocket close message enabled a DoS attack. This issue affects Apache Tomcat: from 11.0.0-M5 through 11.0.25, from 10.1.8 through 10.1.59, from 9.0.74 through 9.0.121. The following versions were EOL at the time the CVE was created but are known to be affected: from 8.5.88 through 8.5.100. Other unsupported versions may also be affected. Users are recommended to upgrade to version 11.0.26, 10.1.60 or 9.0.122, which fix the issue.

EUVD references (1)

https://lists.apache.org/thread/mb1pjjooqytrl6hbvbt3rw1lqwlon4cz

Affected products (1)

Vendor	Product	Versions	Platforms
Apache Software Foundation	Apache Tomcat	`11.0.0-M5` (affected), `10.1.8` (affected), `9.0.74` (affected), `8.5.88` (affected), `0` (unaffected)	—

Vendor references (1)

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

https://lists.apache.org/thread/mb1pjjooqytrl6hbvbt3rw1lqwlon4cz vendor-advisory

Web references (0)

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

No web references attached yet.

NVD-tagged references (2)

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

http://www.openwall.com/lists/oss-security/2026/09/23/24 af854a3a-2127-422b-91ae-364da2661108
https://lists.apache.org/thread/mb1pjjooqytrl6hbvbt3rw1lqwlon4cz security@apache.org

Remediations (10)

CVE-2026-77791 - HIGH Vulnerability - AnonHaven

web:anonhaven.com

The following versions were EOL at the time the CVE was created but are known to be affected: from 8.5.88 through 8.5.100. Other unsupported versions may also be affected. Users are recommended to upgrade to version 11.0.26, 10.1.60 or 9.0.122, which fix the issue.

2026-09-24 11:50 UTC
CVE-2026-77791 - Vulnerability Details - OpenCVE

web:app.opencve.io

Remediation No vendor fix or workaround currently provided. OpenCVE Recommended Actions Upgrade Apache Tomcat to version 11.0.26, 10.1.60, or 9.0.122 or later, which contain the fix for this DoS condition.

2026-09-24 11:50 UTC
CVE-2026-77791: Uncontrolled Resource Consumption | CVETodo

web:cvetodo.com

CVE-2026-77791 is an Uncontrolled Resource Consumption vulnerability in Apache Tomcat. Includes technical details, affected versions, and mitigation steps.

2026-09-24 11:50 UTC
CVE-2026-77791 - security-tracker.debian.org

web:security-tracker.debian.org

Vulnerable and fixed packages The table below lists information on source packages.

2026-09-24 11:50 UTC
Microsoft Patch Tracker (September 2026): Exploit-Ranked | Senserva

web:senserva.com

Every Microsoft security patch (KB) and the CVEs it fixes, with severity, CVSS, and CISA KEV status. Cross-linked to the CVE reference.

2026-09-24 11:50 UTC
SAP Security Patch Day - June 2026

web:support.sap.com

SAP security Patch Day Bulletin This post shares the information on security notes that remediate vulnerabilities discovered in SAP products. SAP strongly recommends that the customer visits the support portal and applies patches on priority to protect their SAP landscape. On 9th of June 2026 , SAP security patch day saw the release of 15 new security notes.

2026-09-24 11:50 UTC
CVE-2026-77791 - vulnerability database | Vulners.com

web:vulners.com

CVE-2026-77791 🗓️ 23 Sep 2026 04:20:50 Reported by apache Type cve 🔗 web.nvd.nist.gov 👁 10 Views

2026-09-24 11:50 UTC
CVE-2026-77791 - Detail CVSS, EPSS & CISA Kev | CVE Find

web:www.cvefind.com

Full details for CVE-2026-77791 : technical description, impact, CVSS/EPSS scores, linked CWE, CAPEC, affected CPEs, disclosure date, and mitigation options.

2026-09-24 11:50 UTC
Oracle Critical Patch Update Advisory - July 2026

web:www.oracle.com

This Critical Patch Update contains 1448 new security patches across the product families listed below. Please note that a My Oracle Support (MOS) note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at July 2026 Critical Patch Update: Executive Summary and Analysis.

2026-09-24 11:50 UTC
CVE-2026-77791: Apache Software Foundation Apache Tomcat ... - Rapid7

web:www.rapid7.com

CVE-2026-77791 : Apache Software Foundation Apache Tomcat: Uncontrolled Resource Consumption vulnerability in Apache Tomcat during sending of WebSocket close message enabled a…. View severity, references, and remediation details from Rapid7.

2026-09-24 11:50 UTC

AI Forensic Analysis

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Raw JSON

The full cvelistV5 record. Download as CVE-2026-77791.json.

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