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Security Bulletin: IBM Security Verify Bridge uses relatively weak cryptographic algorithms in two of its functions (CVE-2021-20441)

Security Bulletin


In two instances, IBM Security Verify Bridge (ISVB) uses a relatively weak cryptographic algorithm. (1) If no transport layer security (TLS) preference is specified, ISVB defaults to TLS 1.0 which has known vulnerabilities. (2) When generating a random number during LDAP bind authentication, ISVB chooses an older, less secure randomizer. As of v1.0.5, ISVB is now defaulting to TLS 1.2 and is using a cryptographically strong random number generator.

Vulnerability Details

CVEID:   CVE-2021-20441
DESCRIPTION:   IBM Security Verify Bridge uses weaker than expected cryptographic algorithms that could allow an attacker to decrypt highly sensitive information.
CVSS Base score: 5.9
CVSS Temporal Score: See: for the current score.
CVSS Vector: (CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N)

Affected Products and Versions

Affected Product(s)Version(s)
IBM Security Verify BridgeAll


Log in to IBM X-Force Exchange / App Exchange and download and install IBM Security Verify Bridge v1.0.5 (or later) at

Workarounds and Mitigations


Get Notified about Future Security Bulletins




Gabor Minyo

Change History

12 Feb 2021: Initial Publication

*The CVSS Environment Score is customer environment specific and will ultimately impact the Overall CVSS Score. Customers can evaluate the impact of this vulnerability in their environments by accessing the links in the Reference section of this Security Bulletin.


According to the Forum of Incident Response and Security Teams (FIRST), the Common Vulnerability Scoring System (CVSS) is an "industry open standard designed to convey vulnerability severity and help to determine urgency and priority of response." IBM PROVIDES THE CVSS SCORES ""AS IS"" WITHOUT WARRANTY OF ANY KIND, INCLUDING THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. CUSTOMERS ARE RESPONSIBLE FOR ASSESSING THE IMPACT OF ANY ACTUAL OR POTENTIAL SECURITY VULNERABILITY.

Document Location


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Document Information

Modified date:
09 March 2021