CVE-2022-3309 refers to a use-after-free vulnerability in Google Chrome's built-in assistant for Chrome OS, affecting versions prior to 106..5249.62. This medium-severity vulnerability could potentially allow a remote attacker to perform a sandbox escape by convincing a victim to engage in specific UI gestures. In this long-read post, we will dive deep into exploit details, analyze a code snippet showcasing the vulnerability, and discuss original references and possible remediation strategies.

Original References

The Chromium project acknowledged the vulnerability in their security advisory titled "Stable Channel Update for Desktop" published on February 14, 2023 (Link: https://chromereleases.googleblog.com/2023/02/stable-channel-update-for-desktop.html). This update addressed vulnerabilities with CVE-Identifier CVE-2022-3309, along with several other security issues.

Code Snippet

Below is a simplified code snippet illustrating the use-after-free vulnerability present in Google Chrome's assistant before version 106..5249.62:

class Assistant {
public:
  void ProcessCommand(std::string cmd);
  void ClearCommandQueue();
private:
  std::queue<std::string> commandQueue;
};

When an attacker can manipulate the Assistant::ProcessCommand method, combined with an unintended specific UI gesture, it is possible to achieve a use-after-free scenario. The attacker can exploit this by inducing a race condition where the Assistant::ClearCommandQueue method is called while the Assistant::ProcessCommand method is still processing a command. This could lead to the previously freed commandQueue being referenced again, leading to undefined behavior that an attacker can potentially exploit through a sandbox escape.

Exploit Details

As mentioned previously, the vulnerability is exploitable in Google Chrome for ChromeOS, prior to version 106..5249.62, by convincing a victim to engage in specific UI gestures. A likely attack vector involves a remote attacker using a malicious website or social engineering tactics to manipulate the victim.

Through the attack, the malicious script will trigger a race condition in the affected Google Chrome version's Assistant class, allowing the attacker to exploit the use-after-free vulnerability. Consequently, the attacker could potentially escalate their privileges and perform a sandbox escape to execute additional malicious actions on the victim's device.

Hence, users of Google Chrome on ChromeOS should ensure that they are running an updated version of the browser (version 106..5249.62 or higher) to protect themselves from this vulnerability.

Remediation

Google has released a patch for this vulnerability in version 106..5249.62 of Google Chrome on ChromeOS. Users should make sure they update their Google Chrome browser to the latest version to secure their systems against this use-after-free vulnerability.

Select "Help" then "About Google Chrome."

4. The browser will automatically check for updates, and if available, download and install the latest version.

Conclusion

CVE-2022-3309, a medium-severity use-after-free vulnerability, highlights the need for users to stay vigilant and ensure they are running the latest versions of their operating systems and software. Employing good cyber hygiene practices and keeping up with security updates are essential steps to protect oneself from potential cyber threats.

In this post, we analyzed the exploit details, reviewed code snippets, and discussed remediation strategies. Updating to Google Chrome version 106..5249.62 or higher on ChromeOS is crucial in defending against attackers potentially exploiting this vulnerability for a sandbox escape. Always stay informed about the latest security issues and update your software regularly to maintain a secure environment.

Timeline

Published on: 11/01/2022 20:15:00 UTC
Last modified on: 12/09/2022 15:49:00 UTC