CVE-2026-18531Network attack vector

Session data tampering via weak HMAC secret

Published Aug 5, 2026 · Updated Aug 5, 2026

Weak session signing in IBM Maximo Application Suite 9.0, 9.1, and 9.2 allows remote attackers to tamper with session data. The suite signs session data with a weak HMAC secret, so untrusted values are not protected by a sufficiently strong message-authentication key. No authentication or user interaction is required; IBM has not disclosed how the secret is generated or stored, and the documented consequence is limited to session-data integrity.

CVSS severity5.3
Medium
EPSS probability0.23%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Weak session signing in IBM Maximo Application Suite 9.0, 9.1, and 9.2 allows remote attackers to tamper with session data. The suite signs session data with a weak HMAC secret, so untrusted values are not protected by a sufficiently strong message-authentication key. No authentication or user interaction is required; IBM has not disclosed how the secret is generated or stored, and the documented consequence is limited to session-data integrity.

The record

CVE
CVE-2026-18531
Published
Aug 5, 2026
Updated
Aug 5, 2026
Vendor
IBM
Product
Maximo Application Suite
Classifications
CWE-330, T1606.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 5, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 5, 2026Record 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=9.0
  2. Affected versionversion=9.1
  3. Affected versionversion=9.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

IBM · Maximo Application Suiteversion=9.0; version=9.1; version=9.2

Published CVSS scores

5.3IBM CorporationCVSS: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.

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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-330Use of Insufficiently Random Values
T1606.001Forge Web Credentials: Web Cookies

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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