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Cisco Bug: CSCtd13999 - Bugs in the Path-mtu logic

Last Modified

Feb 13, 2018

Products (1)

  • Cisco IOS

Known Affected Releases


Description (partial)


A device running IOS may pick an incorrect MSS when path-mtu is enabled. The incorrect MSS is lower than what the network path can support.


The bug is triggered when a transit router sends more than one ICMP-too-big messages.
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