CVE-2021-30603Public exploitNetwork attack vector

Heap corruption via WebAudio loader-thread race

Published Aug 26, 2021 · Updated Aug 3, 2024

Data race in WebAudio in Google Chrome before 92.0.4515.159 allows remote attackers to corrupt heap memory via crafted HTML. HRTFDatabaseLoader::WaitForLoaderThreadCompletion posts through and resets the shared loader-thread pointer without serializing concurrent callers. Opening an attacker-controlled page is required; published evidence establishes heap corruption but not a sandbox escape or host-level compromise.

CVSS severity7.5
High
EPSS probability3.87%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Data race in WebAudio in Google Chrome before 92.0.4515.159 allows remote attackers to corrupt heap memory via crafted HTML. HRTFDatabaseLoader::WaitForLoaderThreadCompletion posts through and resets the shared loader-thread pointer without serializing concurrent callers. Opening an attacker-controlled page is required; published evidence establishes heap corruption but not a sandbox escape or host-level compromise.

The record

CVE
CVE-2021-30603
Published
Aug 26, 2021
Updated
Aug 3, 2024
Vendor
Google Cloud
Product
Google Chrome
Classifications
CWE-362, T1203
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 26, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=unspecified <92.0.4515.159

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Google Cloud · Google Chromeversion=unspecified <92.0.4515.159

Published CVSS scores

7.5NIST NVDCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
5.1NIST NVDAV:N/AC:H/Au:N/C:P/I:P/A:P

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-362Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
T1203Exploitation for Client Execution

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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