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CVE-2026-58592 (GCVE-0-2026-58592)

Vulnerability from cvelistv5 – Published: 2026-07-01 19:27 – Updated: 2026-09-11 14:41
VLAI
Title
Ladybird - Web-Reachable Code Execution via Dangling FunctionType Reference in WebAssembly ESM Integration
Summary
Ladybird before commit 2f9dc7e contains a dangling-reference memory-safety flaw in its WebAssembly ESM-integration module loader. When a JavaScript function is imported into a WebAssembly module via the ESM path, WebAssemblyModule.cpp passes a stack-local Wasm::FunctionType by reference to create_host_function, whose host callback captures and later reads that reference; once the ESM link-loop iteration ends the FunctionType is destroyed, leaving the callback with a dangling reference (the normal instantiate path uses a long-lived reference and is not affected). Stale result-type data lets the host callback return an empty result vector for a statically non-empty result, so the destination register retains an attacker-influenced value that is then consumed by the WASM-GC array.set handler, which bit-casts the reference low bits to an ArrayInstance pointer after only a null check, yielding an arbitrary write. A web page can chain this into code execution in the WebContent process. Verified reachable from HTML content without any instrumentation or source modification.
Severity
8.3 (High)
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:H
8.9 (High)
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:A/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
SSVC
Exploitation: poc Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-02 15:27 UTC
CWE
  • CWE-825 - Expired Pointer Dereference
  • CWE-843 - Access of Resource Using Incompatible Type ('Type Confusion')
  • CWE-787 - Out-of-bounds Write
Assigner
References
Impacted products
Vendor Product Version CPE status
LadybirdBrowser Ladybird Affected: 0 , < 2f9dc7e9f35eed67dde3f9e8567d390dc4f0c665 (git)
guessed Create a notification for this product.
Date Public
2026-07-01 00:00
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.

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