CVE-2026-11177: Chrome Omnibox Use-After-Free Heap Corruption Vulnerability

Technical summary

CVE-2026-11177 is a use-after-free (CWE-416) vulnerability in the Omnibox component of Google Chrome versions prior to 149.0.7827.53. When processing certain UI gestures or user interactions on a specially constructed HTML page, the Omnibox fails to maintain valid memory references, allowing an attacker-controlled page to read or write heap memory. The vulnerability sits at the intersection of browser UI handling and JavaScript execution context, where premature object destruction leaves dangling pointers accessible through subsequent Omnibox operations. Chromium's internal assessment classified this as medium severity due to the user interaction requirement, though the CVSS 3.1 assessment reflects the high potential impact if exploitation succeeds.

Business impact

For enterprises, this vulnerability represents a targeted attack vector against Chrome users, particularly those using Chrome for business-critical tasks or accessing sensitive web applications. An attacker with knowledge of the exploitation technique could compromise endpoints without installing malware, directly accessing the user's session data, cached credentials, or local storage. Organizations with strict Chrome deployment policies may face data exfiltration risks if users visit attacker-controlled or compromised websites. The high CVSS score (8.8) reflects the severity of potential compromise: confidentiality, integrity, and availability are all at risk if the vulnerability is exploited successfully.

Affected systems

Google Chrome on Windows, macOS, and Linux systems running versions before 149.0.7827.53 are directly vulnerable. Chrome's tight integration with the operating system means that while the vulnerability exists in the browser itself, compromised Chrome processes on affected systems can potentially access system-level resources depending on OS permission boundaries. Users of Chromium-based browsers derived from the same codebase should also assess exposure. Mobile Chrome versions should be checked against their corresponding version numbering.

Exploitability

Exploitation requires user interaction—specifically, the user must engage in particular UI gestures with the Omnibox while viewing a crafted HTML page. This is not a vulnerability that can be silently triggered by merely loading a page. An attacker would need to either control a website the target visits, compromise a legitimate site, or use social engineering to drive the user to a malicious page. The user interaction barrier reduces the risk of mass exploitation but does not eliminate it; targeted campaigns against high-value individuals or organizations remain viable. The CVSS vector (AV:N/AC:L/PR:N/UI:R) indicates network accessibility and low complexity, meaning once a user is on the malicious page, execution conditions are favorable.

Remediation

Immediate patching is the primary remediation. Users and administrators should update Google Chrome to version 149.0.7827.53 or later as soon as possible. Chrome's automatic update mechanism typically deploys patches within hours of release; verify update completion through the About Google Chrome menu. For managed deployments, administrators should use Chrome Enterprise policies to enforce timely updates. As an interim control, restricting access to untrusted websites or implementing content security policies can reduce exposure, though these do not eliminate the risk. Consider user awareness training about the risks of visiting unverified sites.

Patch guidance

Google Chrome 149.0.7827.53 and later contain the fix for this vulnerability. Automatic updates on consumer Chrome deployments should push this version within 24 hours of its availability. Enterprise customers using managed deployments should immediately push the update through their deployment mechanisms (e.g., ADMX templates, enrollment tokens, or MDM solutions). Verify successful deployment by checking the Chrome version string in About > Google Chrome or through device reporting dashboards. Legacy versions of Chrome should not be relied upon; users on older versions must be transitioned to a supported release cycle. No backward-compatible patches are expected for pre-149 versions.

Detection guidance

Monitor for exploitation attempts by observing unusual Chrome process behavior: elevated CPU or memory usage, unexpected child processes spawned by Chrome, or network connections from Chrome to suspicious destinations. Web application firewalls and endpoint detection and response (EDR) solutions should flag pages attempting to manipulate Omnibox state through unusual JavaScript or iframe interactions. Network signatures for known exploit campaigns may become available through threat intelligence feeds once the vulnerability gains public attention. Examine crash logs (chrome://crashes) on user machines for segmentation faults or memory access violations in Omnibox-related code. Check for evidence of credential theft or unauthorized access following any suspected exploitation attempts.

Why prioritize this

Despite Chromium's classification as medium severity, this vulnerability scores 8.8 on CVSS 3.1 due to the high impact of heap corruption: full compromise of confidentiality, integrity, and availability. Chrome's ubiquity in enterprise environments and its role in accessing cloud-based services and SaaS platforms makes it a high-value target. The requirement for user interaction prevents mass exploitation but does not reduce the severity of successful attacks against targeted users. Organizations should treat this as high priority for patching, particularly for users with access to sensitive systems or data. The fact that it is not yet on the CISA KEV catalog does not reduce urgency; early patching limits the window for attacker development of reliable exploit techniques.

Risk score, explained

The CVSS 3.1 score of 8.8 (HIGH) reflects the confluence of network accessibility (AV:N), low attack complexity (AC:L), and no required privileges (PR:N), combined with the severe impact: high confidentiality loss (C:H), high integrity loss (I:H), and high availability loss (A:H). The user interaction requirement (UI:R) prevents the score from reaching critical (9.0+), but does not substantially reduce real-world risk for targeted attacks. In the context of a use-after-free in a browser's core UI component, successful exploitation directly correlates with arbitrary code execution in the browser's security context, justifying the high impact ratings.

Frequently asked questions