CVE-2026-8963

Description

Spoofing issue in the Web Speech component. This vulnerability was fixed in Firefox 151 and Thunderbird 151.

Overview

State: PUBLISHED
Assigner (CNA): mozilla
CVSS severity: high
CVSS score: 7.5 / 10
CVSS vector: AV:N/AC:L/Au:N/C:N/I:C/A:N
Effective score: 7.5 / 10 HIGH source: CNA overview
CWE(s): —
Reserved: 2026-05-19
Published: 2026-05-19 12:30 UTC
Last updated: 2026-05-19 17:10 UTC
Source: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/8xxx/CVE-2026-8963.json
Linked Threat: CVE-2026-8963 — CVE-2026-8963

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: 2026-05-19 14:16:52 UTC
NVD last modified: 2026-05-20 14:57:19 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:H/A:N
Exploitability subscore: 3.9 / 10
Impact subscore: 3.6 / 10
EPSS score: 0.0003 (probability of exploitation in next 30 days)
EPSS percentile: 8.31% vs all CVEs — higher = more likely to be exploited, as of 2026-05-24

NVD-assigned CWE(s): CWE-290 (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-2026-30914
Assigner: mozilla
Published: May 19, 2026, 12:30:06 PM
Updated: May 19, 2026, 5:10:53 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:H/A:N
EUVD-reported EPSS: 0.0400
Aliases: GHSA-7f47-q24v-32rc

ENISA description: Spoofing issue in the Web Speech component. This vulnerability was fixed in Firefox 151 and Thunderbird 151.

EUVD references (3)

Affected products (2)

Vendor	Product	Versions	Platforms
Mozilla	Firefox	`151` (unaffected)	—
Mozilla	Thunderbird	`151` (unaffected)	—

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:mozilla:firefox:*:*:*:*:-:*:*:*
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:-:*:*:*

Vendor references (3)

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

Web references (11)

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

https://nvd.nist.gov/vuln/detail/CVE-2026-8963 tenable:nvd.nist.gov
https://bugzilla.mozilla.org/show_bug.cgi?id=2021222 tenable:bugzilla.mozilla.org
https://www.first.org/epss/ tenable:www.first.org
https://www.mozilla.org/security/advisories/mfsa2026-46/ tenable:www.mozilla.org
https://www.mozilla.org/security/advisories/mfsa2026-50/ tenable:www.mozilla.org
http://www.mozilla.org/security/announce/2026/mfsa2026-50.html rapid7:www.mozilla.org
https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-30914 rapid7:euvd.enisa.europa.eu
http://www.mozilla.org/security/announce/2026/mfsa2026-46.html rapid7:www.mozilla.org
https://attackerkb.com/topics/CVE-2026-8963 rapid7:attackerkb.com
http://cwe.mitre.org/data/definitions/290.html rapid7:cwe.mitre.org
https://www.cve.org/CVERecord?id=CVE-2026-8963 rapid7:www.cve.org

NVD-tagged references (3)

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://bugzilla.mozilla.org/show_bug.cgi?id=2021222 security@mozilla.org Permissions Required
https://www.mozilla.org/security/advisories/mfsa2026-46/ security@mozilla.org Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-50/ security@mozilla.org Vendor Advisory

Remediations (17)

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 ...

2026-05-24 12:02 UTC
Six Patch Management Best Practices [Updated 2026]

web:heimdalsecurity.com

Explore six essential patch management best practices for 2026 to keep your systems secure, up to date, and protected from vulnerabilities.

2026-05-24 12:02 UTC
Nvd - Cve-2026-8963

web:nvd.nist.gov

An official website of the United States government Here's how you know

2026-05-24 12:02 UTC
Addressing Exchange Server May 2026 vulnerability CVE-2026-42897

web:techcommunity.microsoft.com

We wanted to tell you how to address the Exchange Server May 2026 vulnerability CVE - 2026 -42897.

2026-05-24 12:02 UTC
CVE-2026-8963 | Ubuntu

web:ubuntu.com

Ubuntu is an open source software operating system that runs from the desktop, to the cloud, to all your internet connected things.

2026-05-24 12:02 UTC
Linux faces its largest security threat in years—here's how to deal ...

web:www.howtogeek.com

Here's the list of mitigation solutions available as we go to publication: Ubuntu Red Hat Enterprise Linux SUSE The Red Hat team warns that there may be a "performance impact" for any task that requires Linux kernel cryptograpic features, so you might notice the effects until a patch lets you restore the relevant processes.

2026-05-24 12:02 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.

2026-05-24 12:02 UTC
CVE-2026-8963 - High Vulnerability - TheHackerWire

web:www.thehackerwire.com

CVE-2026-8963 is a High severity vulnerability (CVSS 7.5). Spoofing issue in the Web Speech component. This vulnerability was fixed in Firefox 151 and Thunderbird 151.

2026-05-24 12:02 UTC
Quantifying 2026 Routinely Targeted Vulnerabilities (So Far)

web:www.vulncheck.com

VulnCheck identified 25 CVEs disclosed in 2026 that have been routinely targeted by adversaries and researchers so far this year, drawing from a global body of exploit code and exploitation data.

2026-05-24 12:02 UTC
IBM WebSphere Server Vulnerable to Remote Code Execution Attack Via ...

web:cybersecuritynews.com

IBM has issued remediation guidance and strongly recommends immediate action. Organizations are advised to apply interim fixes that address APAR PH71342 after upgrading to the required minimum fix pack levels.

2026-06-03 22:32 UTC
Nvd - Cve-2026-20963

web:nvd.nist.gov

An official website of the United States government Here's how you know

2026-06-03 22:32 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.

2026-06-03 22:32 UTC
CISA warns of active exploitation of Microsoft SharePoint vulnerability ...

web:www.helpnetsecurity.com

CVE - 2026 -20963, a remote code execution (RCE) SharePoint vulnerability Microsoft fixed in January 2026 , is being exploited by attackers.

2026-06-03 22:32 UTC
Microsoft Patch Tuesday - May 2026 - Lansweeper

web:www.lansweeper.com

Which vulnerabilities, issues, and other things did Microsoft update? Discover what's new using Lansweeper's Patch Tuesday May 2026 summary.

2026-06-03 22:32 UTC
CISA Warns of Attacks Exploiting Recent SharePoint Vulnerability

web:www.securityweek.com

The SharePoint remote code execution vulnerability CVE - 2026 -20963, which Microsoft patched in January, has been exploited in the wild. The vulnerability, tracked as CVE - 2026 -20963, was disclosed on January 13, when Microsoft released its January 2026 Patch Tuesday updates. CISA added CVE - 2026 -20963 ...

2026-06-03 22:32 UTC
VirusTotal - Home

web:www.virustotal.com

VirusTotal is a platform for scanning files and URLs for viruses, malware, and other threats using multiple antivirus engines.

2026-06-03 22:32 UTC
Patch Tuesday June 2026: Security Updates & CVE Analysis

web:zecurit.com

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

2026-06-03 22:32 UTC

AI Forensic Analysis

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Raw JSON

The full cvelistV5 record. Download as CVE-2026-8963.json.

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