CVE-2026-85046 + CVE-2026-87491

Was doing a ton of reading over at https://github.com/Serotav/Writeups.

Decided to combine 85046 with 87491 and bake in some WASM at the same time.

Went and re-did a stage1.js for an eventual ubuntu LPE I'm cooking.

The basics:

• Confuse packed object and integer arrays during sort().
• Skip a write barrier and reclaim a young object with a fake array.
• Corrupt a Float64Array to read and write the V8 cage.
• Forge a Wasm exception getter using the private exception symbol.
• Change a function table while optimized code assumes no side effects.
• Execute a new target with the old instance's trusted metadata.
• Alias memory index 6 with the executable Wasm jump table.
• Overwrite compiled Wasm code and invoke it.

Run ./run.py /path/to/chrome. It serves run.html, makes up to five fresh-profile attempts, and exits as soon as it captures PWNED 2026 from the renderer. Each attempt is limited to 20 seconds.

To go any further you'd have to have an local priv esc of sorts.