Google fixes fifth actively exploited Chrome zero

Google Chrome's V8 JavaScript engine, in versions prior to 120.0.6099.224, contains an out-of-bounds memory access flaw (CWE-787 out-of-bounds write / CWE-125 out-of-bounds read) that is triggered when a user visits a specially crafted HTML page. A remote attacker who lures a victim to such a page can potentially corrupt the heap and execute code in the context of the browser. Successful exploitation could lead to exposure of sensitive information, data tampering, or denial of service (CVSS 3.1: 8.8 High; user interaction is required). Anyone running a vulnerable Chrome/Chromium build is affected, including downstream products that embed V8, such as Fedora's Chromium/Chrome packages and Couchbase Server. The flaw is being actively exploited in the wild: CISA added it to the Known Exploited Vulnerabilities catalog on 2024-01-17, and news coverage describes it as one of Google's actively exploited Chrome zero-days patched in January 2024.

Do: Update Google Chrome to 120.0.6099.224 or later (and restart the browser so the new version is fully loaded); verify fleet versions via Chrome's version reporting if managing enterprise deployments. Fedora users should install the updated chromium/chrome packages via the distribution's update channel, and Couchbase Server operators should apply the vendor's guidance. Because the flaw is on CISA's KEV catalog, federal and other regulated environments are required to apply vendor mitigations promptly; the only effective mitigation is patching, as no public PoC or alternate workaround is documented.

Type Confusion in WebAssembly in Google Chrome prior to 123.0.6312.86 allowed a remote attacker to execute arbitrary code via a crafted HTML page. (Chromium security severity: High)

Out of bounds memory access in V8 in Google Chrome prior to 123.0.6312.105 allowed a remote attacker to perform arbitrary read/write via a crafted HTML page. (Chromium security severity: High)

CVE-2024-4671 is a use-after-free (CWE-416) in the Visuals component of Google Chrome and Chromium, fixed in Chrome 124.0.6367.201. It is triggered via a crafted HTML page, but the attacker must already have compromised the browser's renderer process, so this flaw is typically chained with a renderer exploit rather than used standalone. Successful exploitation enables a sandbox escape, letting the attacker break out of Chrome's renderer sandbox and gain broader access to the system beyond the browser tab. All users of Google Chrome versions prior to 124.0.6367.201 are affected, and per CISA's CPE data, Fedora's packaged Chromium builds are also in scope. The flaw was added to CISA's Known Exploited Vulnerabilities catalog on 2024-05-13, indicating active exploitation in the wild; no public proof-of-concept is known, EPSS estimates an 8.3% chance of exploitation within 30 days (95th percentile), and ransomware association is unknown.

Do: Update Google Chrome to 124.0.6367.201 or later (verify via chrome://settings/help, since Chrome auto-updates may lag), and update Fedora's chromium package to the fixed build; CISA KEV requires federal agencies to apply the vendor fix on the mandated timeline. Because this sandbox escape must be chained with a renderer compromise, defenders should treat any unpatched Chrome deployment as exposed and confirm via EDR logs whether suspicious renderer-process activity occurred; enterprise admins should push the update through managed-browser channels immediately.