CVE-2026-12321 (GCVE-0-2026-12321)

Vulnerability from cvelistv5 – Published: 2026-06-16 11:52 – Updated: 2026-06-16 16:08
VLAI
Title
JIT miscompilation in the JavaScript: WebAssembly component
Summary
JIT miscompilation in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 152 and Thunderbird 152.
Severity
5.4 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-670 - Always-Incorrect Control Flow Implementation
Assigner
References
Impacted products
Vendor Product Version
Mozilla Firefox Unaffected: 152 , ≤ * (rpm)
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Mozilla Thunderbird Unaffected: 152 , ≤ * (rpm)
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Credits
JunYoung Park
Show details on NVD website
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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.


Detection rules are retrieved from Rulezet.