CVE-2021-20494Network attack vector

Authenticated heap overflow crashes adapter service

Published Jun 28, 2021 · Updated Sep 17, 2024

Heap-based buffer overflow in IBM Security Identity Manager Adapters 6.0 and 7.0 allows remote authenticated users to crash the service. Adapter request handling applies improper bounds to untrusted input, permitting a heap overwrite when an authenticated request exceeds the expected buffer. The consequence is service interruption through a crash; exploitation requires authenticated access to the adapter interface and does not provide a documented confidentiality or integrity impact.

CVSS severity6.5
Medium
EPSS probability1.13%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Heap-based buffer overflow in IBM Security Identity Manager Adapters 6.0 and 7.0 allows remote authenticated users to crash the service. Adapter request handling applies improper bounds to untrusted input, permitting a heap overwrite when an authenticated request exceeds the expected buffer. The consequence is service interruption through a crash; exploitation requires authenticated access to the adapter interface and does not provide a documented confidentiality or integrity impact.

The record

CVE
CVE-2021-20494
Published
Jun 28, 2021
Updated
Sep 17, 2024
Vendor
IBM
Product
IBM Security Verify Governance Identity Manager Adapters
Classifications
CWE-787, T1499.002
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 28, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 17, 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=6.0
  2. Affected versionversion=7.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

IBM · IBM Security Verify Governance Identity Manager Adaptersversion=6.0; version=7.0

Published CVSS scores

6.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
4.0NIST NVDAV:N/AC:L/Au:S/C:N/I:N/A:P

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-787Out-of-bounds Write
T1499.002Endpoint Denial of Service: Service Exhaustion

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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