CVE-2025-2783

CVE-2025-2783 is a high-severity sandbox escape in Google Chrome on Windows, caused by an incorrect handle being provided in unspecified circumstances in Mojo, Chrome's inter-process communication layer. It is triggered remotely through a malicious file and requires user interaction; an attacker who has code running inside Chrome's sandboxed renderer can abuse the handle flaw to break out of the Windows sandbox and gain broader access to the host (CVSS scope change with high impact to confidentiality, integrity, and availability). All Google Chrome versions on Windows prior to 134.0.6998.177 are affected, per the vendor fix referenced by CISA. The flaw was added to CISA's Known Exploited Vulnerabilities catalog on 2025-03-27, and related reporting links it to active exploitation in the ForumTroll APT's phishing campaign against Russian scholars using fake eLibrary emails; ransomware use is unknown. No public proof-of-concept is known, and EPSS assigns a 9.2% probability of exploitation within 30 days (95th percentile).

What to do: Update Google Chrome on Windows to 134.0.6998.177 or later immediately and verify deployed browser versions across endpoints; the flaw is in the CISA KEV catalog, so federal agencies must apply vendor mitigations per BOD 22-01 timelines. Because exploitation is tied to malicious files delivered via phishing (e.g., the ForumTroll fake-eLibrary campaign), prioritize patching for users who open untrusted attachments and links, and hunt for associated phishing emails.