CVE-2026-74967Network attack vector

Cross-origin data access and modification during playback

Published Aug 18, 2026 · Updated Aug 18, 2026

Same-origin policy bypass in Mozilla Firefox and Thunderbird allows remote attackers to read or alter cross-origin data during media playback. The public advisory identifies the Audio/Video Playback component, but Mozilla has not disclosed the incorrect operation because the linked bug remains restricted. Exploitation requires user interaction with attacker-controlled content, and the published assessment limits the consequence to cross-origin confidentiality and integrity.

CVSS severity5.4
Medium
EPSS probability0.12%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Same-origin policy bypass in Mozilla Firefox and Thunderbird allows remote attackers to read or alter cross-origin data during media playback. The public advisory identifies the Audio/Video Playback component, but Mozilla has not disclosed the incorrect operation because the linked bug remains restricted. Exploitation requires user interaction with attacker-controlled content, and the published assessment limits the consequence to cross-origin confidentiality and integrity.

The record

CVE
CVE-2026-74967
Published
Aug 18, 2026
Updated
Aug 18, 2026
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-346
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 18, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 18, 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

5.4CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
6.1Oracle LinuxCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/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-346Origin Validation Error

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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