CVE-2021-29859

Physical session takeover via incomplete logout revocation

Published May 2, 2022 · Updated Sep 16, 2024

Improper session revocation in IBM Cloud Pak for Business Automation allows physically proximate attackers to reuse a logged-out user session. The User Management Service insufficiently validates logout state and fails to fully revoke another user session when that user logs out. Affected base releases are 18.0.0 through 18.0.2, 19.0.1 through 19.0.3, 20.0.1 through 20.0.3, and 21.0.1 through 21.0.3; physical access is required.

CVSS severity3.5
Low
EPSS probability0.26%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper session revocation in IBM Cloud Pak for Business Automation allows physically proximate attackers to reuse a logged-out user session. The User Management Service insufficiently validates logout state and fails to fully revoke another user session when that user logs out. Affected base releases are 18.0.0 through 18.0.2, 19.0.1 through 19.0.3, 20.0.1 through 20.0.3, and 21.0.1 through 21.0.3; physical access is required.

The record

CVE
CVE-2021-29859
Published
May 2, 2022
Updated
Sep 16, 2024
Vendor
IBM
Product
Cloud Pak for Business Automation
Classifications
Unavailable
Attack vector
physical
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 2, 2022CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 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=18.0.0
  2. Affected versionversion=18.0.1
  3. Affected versionversion=18.0.2
  4. Affected versionversion=19.0.1
  5. Affected versionversion=19.0.2
  6. Affected versionversion=19.0.3
  7. Affected versionversion=20.0.1
  8. Affected versionversion=20.0.2
  9. Affected versionversion=20.0.3
  10. Affected versionversion=21.0.1
  11. Affected versionversion=21.0.2
  12. Affected versionversion=21.0.3

What conditions does exploitation require?

Attack vectorphysical
Required privilegesunauthenticated

What is affected?

IBM · Cloud Pak for Business Automationversion=18.0.0; version=18.0.1; version=18.0.2; version=19.0.1; version=19.0.2; version=19.0.3; version=20.0.1; version=20.0.2; version=20.0.3; version=21.0.1; version=21.0.2; version=21.0.3

Published CVSS scores

6.8NIST NVDCVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
4.6NIST NVDAV:L/AC:L/Au:N/C:P/I:P/A:P
3.5IBM CorporationCVSS:3.0/AV:P/AC:L/PR:N/UI:N/S:U/C:L/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)
Vectorphysical
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.

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Technologies

Your stack

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Your stack

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