8.9
HIGH CVSS 4.0
CVE-2026-58592
Ladybird - Web-Reachable Code Execution via Dangling FunctionType Reference in WebAssembly ESM Integration
Description

Ladybird 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.

INFO

Published Date :

July 1, 2026, 7:27 p.m.

Last Modified :

July 1, 2026, 7:27 p.m.

Remotely Exploit :

Yes !

Source :

VulnCheck
Affected Products

The following products are affected by CVE-2026-58592 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 4.0 HIGH 83251b91-4cc7-4094-a5c7-464a1b83ea10
Solution
Address dangling-reference flaw in WebAssembly ESM integration to prevent arbitrary write.
  • Update Ladybird to the latest version.
  • Apply security patches for WebAssembly module loader.
  • Review host callback capture logic.
  • Ensure FunctionType references remain valid.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-58592 vulnerability anywhere in the article.

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.