CVE-2021-30591Network attack vector

Heap corruption via File System API use-after-free

Published Aug 26, 2021 · Updated Aug 3, 2024

Use after free in Google Chrome's File System API before 92.0.4515.131 allows remote attackers to corrupt heap memory via crafted HTML. Google's public advisory identifies the affected API but does not disclose the object-lifetime error or operation that reuses freed memory. The attack requires a user to load attacker-controlled HTML, and the public record does not establish whether exploitation escapes Chrome's sandbox.

CVSS severity8.8
High
EPSS probability2.52%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Use after free in Google Chrome's File System API before 92.0.4515.131 allows remote attackers to corrupt heap memory via crafted HTML. Google's public advisory identifies the affected API but does not disclose the object-lifetime error or operation that reuses freed memory. The attack requires a user to load attacker-controlled HTML, and the public record does not establish whether exploitation escapes Chrome's sandbox.

The record

CVE
CVE-2021-30591
Published
Aug 26, 2021
Updated
Aug 3, 2024
Vendor
Google Cloud
Product
Google Chrome
Classifications
CWE-416, 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 <92.0.4515.131

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Google Cloud · Google Chromeversion=unspecified <92.0.4515.131

Published CVSS scores

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 exploitUnconfirmed

Weakness, pattern, technique

CWE-416Use After Free
T1203Exploitation for Client Execution

Public exploit references

No public exploit references are available in this record.

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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