CVE-2026-74961Network attack vector

Information disclosure via Web Audio side channel

Published Aug 18, 2026 · Updated Aug 20, 2026

Information disclosure in Mozilla Firefox and Thunderbird before 154 allows remote attackers to infer data through a Web Audio side channel. Mozilla has not published which Web Audio operation exposes the signal or what input causes the observable discrepancy. No authentication or user interaction is required; the specific exposed data and operational consequence remain undisclosed.

CVSS severity9.1
Critical
EPSS probability0.25%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Information disclosure in Mozilla Firefox and Thunderbird before 154 allows remote attackers to infer data through a Web Audio side channel. Mozilla has not published which Web Audio operation exposes the signal or what input causes the observable discrepancy. No authentication or user interaction is required; the specific exposed data and operational consequence remain undisclosed.

The record

CVE
CVE-2026-74961
Published
Aug 18, 2026
Updated
Aug 20, 2026
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-203
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 18, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 20, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

9.1CISA ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-203Observable Discrepancy

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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