CVE-2021-2161Network attack vector

Unauthenticated modification of runtime-accessible data

Published Apr 22, 2021 · Updated Sep 26, 2024

A Libraries flaw in Oracle Java SE 7u291, 8u281, 11.0.10, and 16 allows remote attackers to modify Java-accessible data. Oracle has not disclosed the affected library or the incorrect operation it performs on untrusted input. The flaw also affects Java SE Embedded 8u281 and GraalVM Enterprise Edition 19.3.5, 20.3.1.2, and 21.0.0.2 when untrusted code runs under the Java sandbox or untrusted data reaches a Libraries API, allowing creation, deletion, or modification of critical or all accessible data.

CVSS severity5.9
Medium
EPSS probability3.13%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

A Libraries flaw in Oracle Java SE 7u291, 8u281, 11.0.10, and 16 allows remote attackers to modify Java-accessible data. Oracle has not disclosed the affected library or the incorrect operation it performs on untrusted input. The flaw also affects Java SE Embedded 8u281 and GraalVM Enterprise Edition 19.3.5, 20.3.1.2, and 21.0.0.2 when untrusted code runs under the Java sandbox or untrusted data reaches a Libraries API, allowing creation, deletion, or modification of critical or all accessible data.

The record

CVE
CVE-2021-2161
Published
Apr 22, 2021
Updated
Sep 26, 2024
Vendor
Oracle Corporation
Product
Java Platform, Standard Edition (Java SE)
Classifications
Unavailable
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 22, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 26, 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=Java SE:11.0.10
  2. Affected versionversion=Java SE:16
  3. Affected versionversion=Java SE:7u291
  4. Affected versionversion=Java SE:8u281
  5. Affected versionversion=Java SE Embedded:8u281
  6. Affected versionversion=Oracle GraalVM Enterprise Edition:19.3.5
  7. Affected versionversion=Oracle GraalVM Enterprise Edition:20.3.1.2
  8. Affected versionversion=Oracle GraalVM Enterprise Edition:21.0.0.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Oracle Corporation · Java Platform, Standard Edition (Java SE)version=Java SE:11.0.10; version=Java SE:16; version=Java SE:7u291; version=Java SE:8u281; version=Java SE Embedded:8u281; version=Oracle GraalVM Enterprise Edition:19.3.5; version=Oracle GraalVM Enterprise Edition:20.3.1.2; version=Oracle GraalVM Enterprise Edition:21.0.0.2

Published CVSS scores

5.9Oracle CorporationCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N

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 exploitUnconfirmed

Weakness, pattern, technique

No sourced classifications are available.

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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