CVE-2026-74984Network attack vector

Unspecified impact via JavaScript-engine race condition

Published Aug 18, 2026 · Updated Aug 20, 2026

A JavaScript-engine race condition in Firefox and Thunderbird before 154 allows remote attackers to cause an unspecified impact. Mozilla has not published the specific JavaScript-engine locus or unsynchronized operation; the flaw also affects both ESR products before 153.1. Exploitation requires user interaction with remote content, but the public record does not identify the resulting operation or concrete consequence.

CVSS severity6.8
Medium
EPSS probability0.19%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

A JavaScript-engine race condition in Firefox and Thunderbird before 154 allows remote attackers to cause an unspecified impact. Mozilla has not published the specific JavaScript-engine locus or unsynchronized operation; the flaw also affects both ESR products before 153.1. Exploitation requires user interaction with remote content, but the public record does not identify the resulting operation or concrete consequence.

The record

CVE
CVE-2026-74984
Published
Aug 18, 2026
Updated
Aug 20, 2026
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-362
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

6.8CISA ADPCVSS:3.1/AV:N/AC:H/PR:N/UI:R/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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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-362Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

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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