Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata – not a confirmed exploit chain
-
AccessSend malicious WebRTC signaling message
-
ExploitTrigger resource exhaustion in signaling parser
-
ExecutionConsume excessive CPU/memory
-
ImpactCrash Firefox process
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A06:2025 - Insecure Design
ASVS 5.0
V2 - Validation and Business Logic Resource consumption limits
MITRE ATT&CK
1 technique across 1 tactic: Impact The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Exploitation Conditions | Remote unauthenticated attacker can trigger denial-of-service against Firefox < 149 or Firefox ESR < 140.9 via crafted WebRTC signaling traffic. No user interaction required. Affects default Firefox installations with WebRTC enabled. |
| Impact | The vulnerability presents a moderate real-world risk despite the absence of a CVSS score. The attack vector is network-based and requires minimal privileges (an attacker can initiate WebRTC connections to trigger signaling exchanges), but the impact is limited to availability (denial-of-service) rather than confidentiality or integrity. No CVSS vector or EPSS score is currently available, and there is no indication the vulnerability is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog or actively exploited in the wild. The lack of a publicly disclosed proof-of-concept mitigates immediate exploitation risk. However, the vulnerability affects all users of affected Firefox versions, and the signaling component is accessible to any website or attacker who can deliver WebRTC traffic to the target browser. Real-world impact is likely limited to temporary browser crashes or freezes rather than data compromise, making this a lower-priority concern than memory corruption or remote code execution vulnerabilities. |
| Exploit ScenarioDerived | An attacker hosting a malicious website or controlling a network path could embed WebRTC signaling logic that generates crafted signaling messages designed to trigger the vulnerability. When a user visits the malicious site or their traffic is intercepted, the browser processes the adversarial signaling data, causing the WebRTC component to crash or enter a hung state. This results in a temporary denial-of-service affecting the user's browsing session. The attack requires no special privileges and can be delivered passively through any website capable of initiating WebRTC connections, though the impact is limited to the individual user's browser instance rather than system-wide compromise. |
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Alert meAnalysisAIv1 – Mar 24, 2026
Mozilla Firefox versions prior to 149 and Firefox ESR prior to 140.9 are vulnerable to denial-of-service attacks through the WebRTC signaling component, which an unauthenticated remote attacker can exploit without user interaction to crash affected browsers. The vulnerability stems from improper resource handling and currently has no available patch, leaving users of affected versions at risk of service disruption.
Earlier versions of this analysis (1)
A denial-of-service vulnerability exists in Firefox and Firefox ESR's WebRTC signaling component that allows attackers to crash or hang the browser by exploiting improper handling of WebRTC signaling messages. The vulnerability affects Firefox versions below 149 and Firefox ESR versions below 140.9. An attacker can trigger a denial-of-service condition through maliciously crafted WebRTC signaling traffic, potentially disrupting user sessions or browser functionality.
RemediationAI
Users should upgrade Firefox to version 149 or later and Firefox ESR to version 140.9 or later to remediate this vulnerability. These patched versions are available through Mozilla's official distribution channels and auto-update mechanisms. Organizations managing large Firefox deployments should prioritize patching within their standard change management windows, as the vulnerability does not pose an immediate critical threat. As a temporary workaround pending patch deployment, organizations may restrict users' ability to initiate WebRTC connections by disabling WebRTC in privacy settings (via about:config, setting media.peerconnection.enabled to false), though this will disable legitimate real-time communication features. For additional guidance, refer to Mozilla's security advisories at https://www.mozilla.org/security/advisories/mfsa2026-20/ and https://www.mozilla.org/security/advisories/mfsa2026-22/.
Affected VersionsENISA
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 2 packages in euvd
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
The vulnerability resides in the WebRTC signaling layer, which is responsible for establishing peer-to-peer connections by exchanging session descriptions and ICE candidates between endpoints. WebRTC signaling is a critical component of real-time communication in modern browsers and is implemented across both Mozilla Firefox (cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*) and Firefox ESR (cpe:2.3:a:mozilla:firefox_esr:*:*:*:*:*:*:*:*). The root cause appears to be improper input validation or resource management in the signaling message processing logic, likely falling under CWE categories related to improper input validation or denial-of-service mechanisms. When processing malformed or adversarially crafted signaling messages, the browser fails to handle the condition safely, leading to resource exhaustion or infinite loops.
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Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Primary rating from NVD.
CVSS VectorNVD
Lifecycle Timeline
2DescriptionCVE.org
Denial-of-service in the WebRTC: Signaling component. This vulnerability affects Firefox < 149 and Firefox ESR < 140.9.
Executive ViewAI
CVE-2026-4704 presents notable security risk, a resource exhaustion vulnerability rated CVSS 7.5. Exploitation could cause service disruption or denial of service, impacting availability for legitimate users. Organizations should apply vendor updates when available and consider compensating controls in the interim.
Apply vendor patch. If immediate patching is not feasible: (1) Implement network-level access controls to limit exposure; (2) Enable enhanced monitoring and alerting; (3) Apply principle of least privilege.
Threat Intelligence Overview
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Denial of Service attacks render applications or systems unavailable by overwhelming resources or triggering failure conditions.
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Same weakness CWE-400 – Uncontrolled Resource Consumption
View allSame technique Denial Of Service
View allVendor StatusVendor
Debian
| Release | Status | Fixed Version | Urgency |
|---|---|---|---|
| sid | vulnerable | 148.0.2-1 | - |
| (unstable) | fixed | (unfixed) | - |
| Release | Status | Fixed Version | Urgency |
|---|---|---|---|
| bullseye | vulnerable | 115.14.0esr-1~deb11u1 | - |
| bullseye (security) | vulnerable | 140.8.0esr-1~deb11u1 | - |
| bookworm | vulnerable | 128.14.0esr-1~deb12u1 | - |
| bookworm (security) | vulnerable | 140.8.0esr-1~deb12u1 | - |
| trixie (security), trixie | vulnerable | 140.8.0esr-1~deb13u1 | - |
| forky, sid | vulnerable | 140.8.0esr-1 | - |
| (unstable) | fixed | (unfixed) | - |
SUSE
Severity: High| Product | Status |
|---|---|
| Image SLES15-SP5-SAP-Azure-LI-BYOS Image SLES15-SP5-SAP-Azure-LI-BYOS-Production Image SLES15-SP5-SAP-Azure-VLI-BYOS Image SLES15-SP5-SAP-Azure-VLI-BYOS-Production Image SLES15-SP6-SAP-Azure-LI-BYOS Image SLES15-SP6-SAP-Azure-LI-BYOS-Production Image SLES15-SP6-SAP-Azure-VLI-BYOS Image SLES15-SP6-SAP-Azure-VLI-BYOS-Production Image SLES15-SP7-SAP-Azure-LI-BYOS-Production Image SLES15-SP7-SAP-Azure-VLI-BYOS-Production | Affected |
| SUSE Liberty Linux 10 | Fixed |
| SUSE Liberty Linux 8 | Fixed |
| SUSE Liberty Linux 9 | Fixed |
| SUSE Linux Enterprise Desktop 15 SP7 SUSE Linux Enterprise Server 15 SP7 SUSE Linux Enterprise Server for SAP Applications 15 SP7 | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP7 SUSE Linux Enterprise Module for Desktop Applications 15 SP7 | Fixed |
| SUSE Linux Enterprise Module for Package Hub 15 SP7 | Fixed |
| SUSE Linux Enterprise Server 12 SP5-LTSS | Fixed |
| SUSE Linux Enterprise Server 15 SP4-LTSS | Fixed |
| SUSE Linux Enterprise Server 15 SP5-LTSS | Fixed |
| SUSE Linux Enterprise Server 15 SP6-LTSS | Fixed |
| SUSE Linux Enterprise Server 16.0 SUSE Linux Enterprise Server for SAP applications 16.0 | Fixed |
| SUSE Linux Enterprise Server LTSS Extended Security 12 SP5 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | Fixed |
| SUSE Linux Enterprise Workstation Extension 15 SP7 | Fixed |
| openSUSE Leap 15.6 | Fixed |
| openSUSE Leap 16.0 | Fixed |
| openSUSE Tumbleweed | Fixed |
| SUSE Linux Enterprise Server 16.0 | Affected |
| SUSE Linux Enterprise Desktop 15 SP7 | Fixed |
| SUSE Linux Enterprise Desktop 15 SP7 | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP7 | Fixed |
| SUSE Linux Enterprise Module for Desktop Applications 15 SP7 | Fixed |
| SUSE Linux Enterprise Module for Package Hub 15 SP7 | Fixed |
| SUSE Linux Enterprise Server 15 SP7 | Fixed |
| SUSE Linux Enterprise Server 15 SP7 | Fixed |
| SUSE Linux Enterprise Server 16.0 | Fixed |
| SUSE Linux Enterprise Server 16.1 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP7 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP7 | Fixed |
| SUSE Linux Enterprise Server for SAP applications 16.0 | Fixed |
| SUSE Linux Enterprise Server for SAP applications 16.1 | Fixed |
| SUSE Linux Enterprise Workstation Extension 15 SP7 | Fixed |
| openSUSE Leap 15.6 | Fixed |
| openSUSE Leap 15.6 | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP4 | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP5 | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS | Fixed |
| SUSE Linux Enterprise Module for Desktop Applications 15 SP4 | Fixed |
| SUSE Linux Enterprise Module for Desktop Applications 15 SP5 | Fixed |
| SUSE Linux Enterprise Module for Desktop Applications 15 SP6 | Fixed |
| SUSE Linux Enterprise Server 12 SP5 | Fixed |
| SUSE Linux Enterprise Server 12 SP5-LTSS | Fixed |
| SUSE Linux Enterprise Server 12 SP5-LTSS Extended Security | Fixed |
| SUSE Linux Enterprise Server 15 SP4 | Fixed |
| SUSE Linux Enterprise Server 15 SP4 | Fixed |
| SUSE Linux Enterprise Server 15 SP4-LTSS | Fixed |
| SUSE Linux Enterprise Server 15 SP5 | Fixed |
| SUSE Linux Enterprise Server 15 SP5 | Fixed |
| SUSE Linux Enterprise Server 15 SP5-LTSS | Fixed |
| SUSE Linux Enterprise Server 15 SP6 | Fixed |
| SUSE Linux Enterprise Server 15 SP6 | Fixed |
| SUSE Linux Enterprise Server 15 SP6-LTSS | Fixed |
| SUSE Linux Enterprise Server LTSS Extended Security 12 SP5 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 12 SP5 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | Fixed |
| SUSE Manager Proxy 4.3 | Fixed |
| SUSE Manager Retail Branch Server 4.3 | Fixed |
| SUSE Manager Server 4.3 | Fixed |
| SUSE CaaS Platform 4.0 | Fixed |
| SUSE Enterprise Storage 6 | Fixed |
| SUSE Enterprise Storage 7 | Fixed |
| SUSE Enterprise Storage 7.1 | Fixed |
| SUSE Linux Enterprise Desktop 12 SP4 | Fixed |
| SUSE Linux Enterprise Desktop 15 | Fixed |
| SUSE Linux Enterprise Desktop 15 SP1 | Fixed |
| SUSE Linux Enterprise Desktop 15 SP2 | Fixed |
| SUSE Linux Enterprise Desktop 15 SP2 | Fixed |
| SUSE Linux Enterprise Desktop 15 SP3 | Fixed |
| SUSE Linux Enterprise Desktop 15 SP3 | Fixed |
| SUSE Linux Enterprise Desktop 15 SP4 | Fixed |
| SUSE Linux Enterprise Desktop 15 SP4 | Fixed |
| SUSE Linux Enterprise Desktop 15 SP5 | Fixed |
| SUSE Linux Enterprise Desktop 15 SP5 | Fixed |
| SUSE Linux Enterprise Desktop 15 SP6 | Fixed |
| SUSE Linux Enterprise Desktop 15 SP6 | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP1 | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP1-ESPOS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP1-LTSS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP2 | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP2-ESPOS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP2-LTSS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP3 | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP3-ESPOS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP3-LTSS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP6 | Fixed |
| SUSE Linux Enterprise High Performance Computing 15-ESPOS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15-LTSS | Fixed |
| SUSE Linux Enterprise Module for Desktop Applications 15 | Fixed |
| SUSE Linux Enterprise Module for Desktop Applications 15 SP1 | Fixed |
| SUSE Linux Enterprise Module for Desktop Applications 15 SP2 | Fixed |
| SUSE Linux Enterprise Module for Desktop Applications 15 SP3 | Fixed |
| SUSE Linux Enterprise Module for Package Hub 15 SP3 | Fixed |
| SUSE Linux Enterprise Module for Package Hub 15 SP4 | Fixed |
| SUSE Linux Enterprise Module for Package Hub 15 SP5 | Fixed |
| SUSE Linux Enterprise Module for Package Hub 15 SP6 | Fixed |
| SUSE Linux Enterprise Point of Sale 12 SP2-CLIENT | Fixed |
| SUSE Linux Enterprise Real Time 15 SP2 | Fixed |
| SUSE Linux Enterprise Real Time 15 SP3 | Fixed |
| SUSE Linux Enterprise Real Time 15 SP4 | Fixed |
| SUSE Linux Enterprise Server 12 SP2-BCL | Fixed |
| SUSE Linux Enterprise Server 12 SP2-ESPOS | Fixed |
| SUSE Linux Enterprise Server 12 SP2-LTSS | Fixed |
| SUSE Linux Enterprise Server 12 SP3-BCL | Fixed |
| SUSE Linux Enterprise Server 12 SP3-ESPOS | Fixed |
| SUSE Linux Enterprise Server 12 SP3-LTSS | Fixed |
| SUSE Linux Enterprise Server 12 SP4 | Fixed |
| SUSE Linux Enterprise Server 12 SP4-ESPOS | Fixed |
| SUSE Linux Enterprise Server 12 SP4-LTSS | Fixed |
| SUSE Linux Enterprise Server 15 | Fixed |
| SUSE Linux Enterprise Server 15 SP1 | Fixed |
| SUSE Linux Enterprise Server 15 SP1-BCL | Fixed |
| SUSE Linux Enterprise Server 15 SP1-LTSS | Fixed |
| SUSE Linux Enterprise Server 15 SP2 | Fixed |
| SUSE Linux Enterprise Server 15 SP2 | Fixed |
| SUSE Linux Enterprise Server 15 SP2-BCL | Fixed |
| SUSE Linux Enterprise Server 15 SP2-LTSS | Fixed |
| SUSE Linux Enterprise Server 15 SP3 | Fixed |
| SUSE Linux Enterprise Server 15 SP3 | Fixed |
| SUSE Linux Enterprise Server 15 SP3-BCL | Fixed |
| SUSE Linux Enterprise Server 15 SP3-LTSS | Fixed |
| SUSE Linux Enterprise Server 15-LTSS | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 12 SP2 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 12 SP3 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 12 SP4 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP1 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP2 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP2 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP3 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP3 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | Fixed |
| SUSE Linux Enterprise Software Development Kit 12 SP4 | Fixed |
| SUSE Linux Enterprise Software Development Kit 12 SP5 | Fixed |
| SUSE Linux Enterprise Workstation Extension 15 SP2 | Fixed |
| SUSE Linux Enterprise Workstation Extension 15 SP3 | Fixed |
| SUSE Linux Enterprise Workstation Extension 15 SP4 | Fixed |
| SUSE Linux Enterprise Workstation Extension 15 SP5 | Fixed |
| SUSE Linux Enterprise Workstation Extension 15 SP6 | Fixed |
| SUSE Manager Proxy 4.0 | Fixed |
| SUSE Manager Proxy 4.1 | Fixed |
| SUSE Manager Proxy 4.2 | Fixed |
| SUSE Manager Retail Branch Server 4.0 | Fixed |
| SUSE Manager Retail Branch Server 4.1 | Fixed |
| SUSE Manager Retail Branch Server 4.2 | Fixed |
| SUSE Manager Server 4.0 | Fixed |
| SUSE Manager Server 4.1 | Fixed |
| SUSE Manager Server 4.2 | Fixed |
| SUSE OpenStack Cloud 7 | Fixed |
| SUSE OpenStack Cloud 8 | Fixed |
| SUSE OpenStack Cloud 9 | Fixed |
| SUSE OpenStack Cloud Crowbar 8 | Fixed |
| SUSE OpenStack Cloud Crowbar 9 | Fixed |
| openSUSE Leap 15.3 | Fixed |
| openSUSE Leap 15.3 | Fixed |
| openSUSE Leap 15.4 | Fixed |
| openSUSE Leap 15.4 | Fixed |
| openSUSE Leap 15.5 | Fixed |
| openSUSE Leap 15.5 | Fixed |
| suse/kiosk/firefox-esr:esr | Fixed |
EUVD-2026-14823
GHSA-2mf6-25gq-26v8
NVD
CVE.org
EPSS
Vulnrichment
VulDB
Exploit-DB