CVE-2026-16365 (GCVE-0-2026-16365)

Vulnerability from cvelistv5 – Published: 2026-07-21 12:37 – Updated: 2026-09-01 21:44
VLAI
Title
Privilege escalation in the DOM: Workers component
Summary
Privilege escalation in the DOM: Workers component. This vulnerability was fixed in Firefox 153, Thunderbird 153, Firefox ESR 140.15, and Thunderbird 140.15.
Severity
8.8 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-24 03:55 UTC
CWE
  • CWE-269 - Improper Privilege Management
  • CWE-284 - Improper Access Control
Assigner
References
Impacted products
Vendor Product Version
Mozilla Firefox Unaffected: 140.15 , ≤ 140.* (rpm)
Unaffected: 153 , ≤ * (rpm)
Create a notification for this product.
Mozilla Thunderbird Unaffected: 140.15 , ≤ 140.* (rpm)
Unaffected: 153 , ≤ * (rpm)
Create a notification for this product.
Credits
Khanh Nguyen
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Related by attack behaviour

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