CVE-2021-29855Network attack vector

Credential disclosure via Mailbox UI script injection

Published Oct 6, 2021 · Updated Sep 17, 2024

Cross-site scripting in IBM Sterling B2B Integrator allows remote authenticated users to expose credentials through its Mailbox UI. The Mailbox UI accepts embedded arbitrary JavaScript and executes it in a trusted session; IBM does not disclose the affected field or code path. Affected releases are 5.2.0.0 through 6.0.3.4 and 6.1.0.0 through 6.1.0.3, and exploitation requires another user's interaction.

CVSS severity5.4
Medium
EPSS probability0.50%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cross-site scripting in IBM Sterling B2B Integrator allows remote authenticated users to expose credentials through its Mailbox UI. The Mailbox UI accepts embedded arbitrary JavaScript and executes it in a trusted session; IBM does not disclose the affected field or code path. Affected releases are 5.2.0.0 through 6.0.3.4 and 6.1.0.0 through 6.1.0.3, and exploitation requires another user's interaction.

The record

CVE
CVE-2021-29855
Published
Oct 6, 2021
Updated
Sep 17, 2024
Vendor
IBM
Product
IBM Sterling B2B Integrator
Classifications
T1059.007
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Oct 6, 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=5.2.0.0
  2. Affected versionversion=6.0.3.4
  3. Affected versionversion=6.1.0.0
  4. Affected versionversion=6.1.0.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

IBM · IBM Sterling B2B Integratorversion=5.2.0.0; version=6.0.3.4; version=6.1.0.0; version=6.1.0.3

Published CVSS scores

5.4IBM X-ForceCVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:C/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)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1059.007Command and Scripting Interpreter: JavaScript

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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