CVE-2021-35560Network attack vector

Client takeover by sandboxed untrusted code

Published Oct 20, 2021 · Updated Sep 6, 2024

Sandbox escape in Oracle Java SE 8u301 Deployment allows remote attackers to take over an affected client through untrusted code. Oracle has not disclosed the named code locus or the incorrect operation performed on that code. Exploitation requires human interaction and a sandboxed Java Web Start application or applet; trusted-code server deployments are not affected.

CVSS severity7.5
High
EPSS probability4.83%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Sandbox escape in Oracle Java SE 8u301 Deployment allows remote attackers to take over an affected client through untrusted code. Oracle has not disclosed the named code locus or the incorrect operation performed on that code. Exploitation requires human interaction and a sandboxed Java Web Start application or applet; trusted-code server deployments are not affected.

The record

CVE
CVE-2021-35560
Published
Oct 20, 2021
Updated
Sep 6, 2024
Vendor
Oracle Corporation
Product
Oracle Java SE
Classifications
T1204
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 20, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 6, 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=8u301

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Oracle Corporation · Oracle Java SEversion=8u301
Oracle Corporation · Java Platform, Standard Edition (Java SE)version=Java SE:8u301

Published CVSS scores

5.1NIST NVDAV:N/AC:H/Au:N/C:P/I:P/A:P
7.5Oracle CorporationCVSS:3.1/AV:N/AC:H/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

T1204User Execution

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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