CVE-2026-17993 in Chrome
Summary
by MITRE • 07/30/2026
Race in Updater in Google Chrome on Windows prior to 151.0.7922.72 allowed a local attacker to perform privilege escalation via a malicious file. (Chromium security severity: Low)
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Analysis
by VulDB Data Team • 07/30/2026
This vulnerability represents a race condition within the Chrome updater component on windows systems, specifically affecting versions prior to 151.0.7922.72. The flaw occurs during the update process when the system fails to properly synchronize access to critical files, creating a window where malicious actors can exploit temporal inconsistencies in file handling operations. The vulnerability falls under the category of privilege escalation attacks as it allows local attackers to elevate their privileges from standard user level to administrative rights through manipulation of updater processes.
The technical implementation of this race condition involves the updater component's failure to properly validate or secure temporary files during the update cycle. When Chrome performs updates on windows systems, it creates temporary files and directories that may be susceptible to manipulation by unauthorized users. The race condition manifests when an attacker can predict or influence the timing of file operations, allowing them to substitute legitimate update files with malicious counterparts. This type of vulnerability is classified as a CWE-367: Time-of-Check to Time-of-Use (TOCTOU) flaw where the system checks for file integrity at one point but modifies or accesses the same resource at a later point.
From an operational impact perspective, this vulnerability presents significant security implications for organizations running affected Chrome versions. Local attackers who already have access to a user account can leverage this weakness to gain elevated privileges without requiring additional exploitation vectors. The attack requires minimal prerequisites since it only necessitates local system access and knowledge of the updater process timing. This makes it particularly dangerous in environments where users may have varying levels of system access or where privilege escalation attacks are difficult to detect through traditional monitoring mechanisms.
The security implications extend beyond simple privilege escalation as this vulnerability could potentially enable attackers to install persistent backdoors, modify system configurations, or access sensitive data that would normally be protected by standard user permissions. The low chromium security severity rating does not diminish the practical impact of this vulnerability since it represents a straightforward path to privilege elevation on vulnerable systems. Organizations should consider implementing immediate mitigations including patching affected Chrome installations, monitoring for unusual updater activity, and reviewing system access controls to limit potential exploitation vectors.
Mitigation strategies should include immediate deployment of Chrome versions 151.0.7922.72 or later where this vulnerability has been addressed through improved file handling synchronization mechanisms. Additionally, system administrators should implement monitoring solutions that detect anomalous updater behavior patterns and establish baseline configurations that minimize the attack surface for such race conditions. The remediation efforts should align with established security frameworks including principles from the attack mitigation tactics defined in the MITRE ATT&CK framework, particularly focusing on privilege escalation techniques and local execution methods that could leverage this vulnerability.