cbcvebase.
CVE-2021-30633
published 2021-10-08

CVE-2021-30633: Use after free in Indexed DB API in Google Chrome prior to 93.0.4577.82 allowed a remote attacker who had compromised the renderer process to potentially…

PriorityP189critical9.6CVSS 3.1
AVNACLPRNUIRSCCHIHAH
KEVITW
CISA Known Exploited Vulnerabilitydue 2021-11-17
Exploited in the wild
EPSS
32.66%
98.1th percentile
Use after free in Indexed DB API in Google Chrome prior to 93.0.4577.82 allowed a remote attacker who had compromised the renderer process to potentially perform a sandbox escape via a crafted HTML page.

Affected

11 ranges
VendorProductVersion rangeFixed in
chromiumchromium>= 0 < 93.0.4577.82-193.0.4577.82-1
chromiumchromium>= 0 < 93.0.4577.82-193.0.4577.82-1
chromiumchromium>= 0 < 93.0.4577.82-193.0.4577.82-1
chromiumchromium>= 0 < 93.0.4577.82-193.0.4577.82-1
debianchromium< chromium 93.0.4577.82-1 (bookworm)chromium 93.0.4577.82-1 (bookworm)
fedoraprojectfedora
fedoraprojectfedora
googlechrome< 93.0.4577.8293.0.4577.82
googlechrome>= unspecified < 93.0.4577.8293.0.4577.82
googlechrome_chrome
msrcmicrosoft_edge

Detection & IOCsextracted from sources · hover to see the quote

  • Vulnerability exists in Google Chrome versions prior to 93.0.4577.82; presence of older versions indicates unpatched exposure to this use-after-free sandbox escape
  • Exploitation requires a compromised renderer process as a prerequisite; monitor for renderer process anomalies combined with Indexed DB API activity as a chained exploitation indicator
  • Vulnerability affects multiple Chromium-based browsers beyond Chrome, including Microsoft Edge and Opera; broaden detection scope accordingly
  • CVE-2021-30633 is tracked in CISA KEV catalog with a remediation due date of 2021-11-17, indicating confirmed in-the-wild exploitation; prioritize detection and patching
  • Chromium bug tracker ID 1247766 is associated with this CVE; can be used to cross-reference patch commits and diff analysis for signature development
  • ·Exploitation requires a pre-compromised renderer process; this is a second-stage sandbox escape, not a direct initial-access vector

CVSS provenance

nvdv3.19.6CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
nvdv2.06.8MEDIUMAV:N/AC:M/Au:N/C:P/I:P/A:P
osv9.6CRITICAL
vulncheck9.6CRITICAL
cisa9.6CRITICAL
vendor_debian9.6CRITICAL
vendor_msrc9.6CRITICAL
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