CVE-2026-6757 (GCVE-0-2026-6757)

Vulnerability from cvelistv5 – Published: 2026-04-21 12:40 – Updated: 2026-05-26 18:07
VLAI
Title
Invalid pointer in the JavaScript: WebAssembly component
Summary
Invalid pointer in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 150, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.
Severity
6.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-824 - Access of Uninitialized Pointer
Assigner
References
Impacted products
Vendor Product Version
Mozilla Firefox Unaffected: 140.10 , ≤ 140.* (rpm)
Unaffected: 150 , ≤ * (rpm)
Create a notification for this product.
Mozilla Thunderbird Unaffected: 140.10 , ≤ 140.* (rpm)
Unaffected: 150 , ≤ * (rpm)
Create a notification for this product.
Credits
Evyatar Ben Asher, Keane Lucas, Nicholas Carlini, Newton Cheng, Daniel Freeman, Alex Gaynor, and Joel Weinberger using Claude from Anthropic
Show details on NVD website
To clipboard 

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Taxonomy of the tags.





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

Author Source Type Date Other

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.


Detection rules are retrieved from Rulezet.