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Cisco Bug: CSCuq86376 - X509SubjectNameMaxLength too small causes phone unable to register

Last Modified

Feb 26, 2019

Products (1)

  • Cisco Unified Communications Manager (CallManager)

Known Affected Releases

10.5(1.10000.7) 9.1(2.10000.28)

Description (partial)


A vulnerability in the Remote Mobile Access Subsystem in the Cisco Unified Communication Manager (CUCM) could allow an unauthenticated, remote
attacker to supply a crafted TLS certificate that may be accepted by the affected device.

The vulnerability is due to improper validation of the SAN field of a TLS certificate. An attacker could exploit this vulnerability by
impersonating a VCS Core device and supplying a certificate signed by a certificate authority trusted by the CUCM, but containing crafted values
within the SAN field.


An affected product with the default configuration running an affected version of software.
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Bug Details Include

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  • Status
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