• Bundled build: Playwright v1.64.0 release notes list Chromium 156.0.8078.4; the v1.64.1 browsers.json pins the same version. Playwright's main branch has already rolled to Chromium 158.0.8127.2, which has not shipped in a release yet.
• What it misses: Chrome 156.0.8078.73/.74 (Oct 27) fixed 52 flaws, including critical CVE-2026-118306 (FileSystem memory corruption, CVSS 3.1 9.6, code execution outside the sandbox via a crafted HTML page), CVE-2026-118331, CVE-2026-118348 and CVE-2026-118344. Google did not report any of them as exploited.
• Sandbox default: Playwright's API docs say chromiumSandbox is false by default, so renderer exploits are not contained by Chromium's sandbox unless you turn it on.

What to do if your agents use Playwright to browse untrusted sites: launch with chromiumSandbox: true, or point Playwright at an up-to-date installed Chrome with channel: 'chrome'; run the agent's browser in a disposable VM or container without your credentials; and update when Playwright releases a newer Chromium. Test suites that only load your own app carry much less risk.