CVE-2021-39056Network attack vector

Authenticated service interruption via crafted EDRSQL request

Published Jan 13, 2022 · Updated Sep 17, 2024

Denial of service in IBM i 7.1 through 7.4 EDRSQL allows remote authenticated users to interrupt service via a crafted request. IBM has not published which EDRSQL request field or processing operation fails when the crafted input is handled. An authenticated EDRSQL session is required, and exploitation affects availability without reported data disclosure or modification.

CVSS severity6.5
Medium
EPSS probability1.31%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Denial of service in IBM i 7.1 through 7.4 EDRSQL allows remote authenticated users to interrupt service via a crafted request. IBM has not published which EDRSQL request field or processing operation fails when the crafted input is handled. An authenticated EDRSQL session is required, and exploitation affects availability without reported data disclosure or modification.

The record

CVE
CVE-2021-39056
Published
Jan 13, 2022
Updated
Sep 17, 2024
Vendor
IBM
Product
IBM i
Classifications
T1499.004
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jan 13, 2022CVE 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=7.1
  2. Affected versionversion=7.2
  3. Affected versionversion=7.3
  4. Affected versionversion=7.4

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

IBM · IBM iversion=7.1; version=7.2; version=7.3; version=7.4

Published CVSS scores

6.5IBM CorporationCVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
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
5.7IBM CorporationCVSS:3.0/UI:N/AV:N/AC:L/S:U/A:H/PR:L/I:N/C:N/RC:C/RL:O/E:U

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

T1499.004Application or System Exploitation

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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