CVE-2021-21160Public exploitNetwork attack vector

Code execution via negative-size WebAudio copy

Published Mar 9, 2021 · Updated Aug 3, 2024

A heap-based buffer overflow in Google Chrome before 89.0.4389.72 allows remote attackers to execute code via a crafted HTML page. AudioDelayDSPKernel::ProcessKRate passes a negative buffer remainder to memcpy as an unsigned size after a runtime switch to k-rate. A victim must visit a malicious site; successful heap grooming converts the out-of-bounds copy into code execution within the browser.

CVSS severity8.8
High
EPSS probability1.91%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

A heap-based buffer overflow in Google Chrome before 89.0.4389.72 allows remote attackers to execute code via a crafted HTML page. AudioDelayDSPKernel::ProcessKRate passes a negative buffer remainder to memcpy as an unsigned size after a runtime switch to k-rate. A victim must visit a malicious site; successful heap grooming converts the out-of-bounds copy into code execution within the browser.

The record

CVE
CVE-2021-21160
Published
Mar 9, 2021
Updated
Aug 3, 2024
Vendor
Google Cloud
Product
Google Chrome
Classifications
CWE-787, CWE-122, T1189, T1203
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 9, 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

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=unspecified <89.0.4389.72

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Google Cloud · Google Chromeversion=unspecified <89.0.4389.72

Published CVSS scores

8.8Cisco TalosCVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
6.8NIST NVDAV:N/AC:M/Au:N/C:P/I:P/A:P
8.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-787Out-of-bounds Write
CWE-122Heap-based Buffer Overflow
T1189Drive-by Compromise
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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