CVE-2021-37973KEV · OVERDUE

Google Chromium Portals Use-After-Free Vulnerability

Critical · published October 8, 2021

Patch now

Confirmed exploited, and the score agrees

CVSS calls it critical at 9.6. It is confirmed in active exploitation. It sits in the 95.8th percentile for exploit probability.

1754
days past CISA
deadline
CVSS v3.1
9.6
EPSS
12%
Percentile
95.8
In the wild
Confirmed
What it is

🔥 A crafty HTML page can turn a remote attacker into a sandbox escape artist, slipping right out of Google Chrome’s protective barriers! 🚨 Think of a secure castle with high walls and guards. If an intruder uses a clever disguise to trick the guards, they can stroll into the castle and wreak havoc — that’s exactly what happens here with this use-after-free vulnerability. An attacker could potentially break free from Chrome's sandbox, gaining access to sensitive resources on the user's system. This might lead to data theft, unauthorized system access, or worse, complete control over the compromised machine — absolutely devastating!

Put simply

Think of a secure castle with high walls and guards. If an intruder uses a clever disguise to trick the guards, they can stroll into the castle and wreak havoc — that’s exactly what happens here with this use-after-free vulnerability. This use-after-free vulnerability in Google Chrome's Portals allows an attacker who has compromised the renderer process to execute arbitrary code outside the restricted environment, effectively escaping the sandbox.

What to do

An attacker could potentially break free from Chrome's sandbox, gaining access to sensitive resources on the user's system. This might lead to data theft, unauthorized system access, or worse, complete control over the compromised machine — absolutely devastating! Update Google Chrome to version 94.0.4606.61 or later immediately to patch this vulnerability. Ensure that all systems running this browser are updated and monitor for any suspicious activity. Don't forget to educate your users about potential phishing attacks that could lead to such exploits! You've got this! Stay vigilant and keep your software up to date for a safer browsing experience. 🛡️

The record
Technical detail
CVSS v3.1
9.6 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.11641 · 95.8th percentile
Published
2021-10-08T21:40Z
KEV added
2021-11-03 · due 2021-11-17
EPSS history
Timeline
  • 03 NOV 00:00Z
    Added to CISA KEV — remediate by Nov 17
    kev
  • 08 OCT 21:40Z
    Use after free in Portals in Google Chrome prior to 94.0.4606.61 allowed a remote attacker who had compromised the renderer process to potentially perform a…
    cvelistv5