CVE-2026-16367Network attack vector

Sandbox escape via invalid pointer handling

Published Jul 21, 2026 · Updated Jul 21, 2026

Invalid-pointer handling in Mozilla Firefox and Thunderbird before 153 allows remote attackers to escape the content sandbox. Mozilla identifies the Disability Access APIs component but has not disclosed the affected function or invalid-pointer operation. No additional configuration gate is public; successful exploitation crosses the sandbox boundary and permits access to the host context.

CVSS severity10.0
Critical
EPSS probability0.38%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Invalid-pointer handling in Mozilla Firefox and Thunderbird before 153 allows remote attackers to escape the content sandbox. Mozilla identifies the Disability Access APIs component but has not disclosed the affected function or invalid-pointer operation. No additional configuration gate is public; successful exploitation crosses the sandbox boundary and permits access to the host context.

The record

CVE
CVE-2026-16367
Published
Jul 21, 2026
Updated
Jul 21, 2026
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-416, CWE-787, CWE-119, T1068
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 21, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 21, 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

10.0CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-416Use After Free
CWE-787Out-of-bounds Write
CWE-119Improper Restriction of Operations within the Bounds of a Memory Buffer
T1068Exploitation for Privilege Escalation

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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