CVE-2021-41041Network attack vector

Bytecode verification bypass via dropped pending exception

Published Apr 27, 2022 · Updated Aug 4, 2024

Type confusion in Eclipse OpenJ9 before 0.32.0 allows remote attackers to invoke unverified Java 8 or 11 methods through MethodHandles. The MethodHandle interpreter fails to check and throw the pending exception returned by initializeClassIfNeeded() after bytecode verification fails. Reachability requires attacker-controlled code to cause MethodHandle invocation of the rejected method; the bounded consequence is bypass of JVM bytecode verification.

CVSS severity5.3
Medium
EPSS probability1.06%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Type confusion in Eclipse OpenJ9 before 0.32.0 allows remote attackers to invoke unverified Java 8 or 11 methods through MethodHandles. The MethodHandle interpreter fails to check and throw the pending exception returned by initializeClassIfNeeded() after bytecode verification fails. Reachability requires attacker-controlled code to cause MethodHandle invocation of the rejected method; the bounded consequence is bypass of JVM bytecode verification.

The record

CVE
CVE-2021-41041
Published
Apr 27, 2022
Updated
Aug 4, 2024
Vendor
The Eclipse Foundation
Product
Eclipse OpenJ9
Classifications
CWE-252, CWE-908, CWE-843
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 27, 2022CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 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 <0.32.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Eclipse Foundation · Eclipse OpenJ9version=unspecified <0.32.0

Published CVSS scores

5.0NIST NVDAV:N/AC:L/Au:N/C:N/I:P/A:N
5.3NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/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

CWE-252Unchecked Return Value
CWE-908Use of Uninitialized Resource
CWE-843Access of Resource Using Incompatible Type ('Type Confusion')

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

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo