CVE-2020-4251Network attack vector

Credential disclosure via Web UI script injection

Published Jun 12, 2020 · Updated Sep 17, 2024

Cross-site scripting in IBM API Connect 5.0.0.0 through 5.0.8.8 allows remote authenticated users to expose credentials through its Web UI. The Web UI embeds user-supplied content as arbitrary JavaScript in trusted pages; IBM has not disclosed the affected field, route, or validation failure. A user account is required to inject the script, and a victim must view the affected interface within a trusted session for the code to execute.

CVSS severity5.4
Medium
EPSS probability0.56%
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 API Connect 5.0.0.0 through 5.0.8.8 allows remote authenticated users to expose credentials through its Web UI. The Web UI embeds user-supplied content as arbitrary JavaScript in trusted pages; IBM has not disclosed the affected field, route, or validation failure. A user account is required to inject the script, and a victim must view the affected interface within a trusted session for the code to execute.

The record

CVE
CVE-2020-4251
Published
Jun 12, 2020
Updated
Sep 17, 2024
Vendor
IBM
Product
API Connect
Classifications
T1056.003
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 12, 2020CVE 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=5.0.0.0
  2. Affected versionversion=5.0.8.8

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

IBM · API Connectversion=5.0.0.0; version=5.0.8.8

Published CVSS scores

5.4IBMCVSS: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

T1056.003Web Portal Capture

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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