This issue is resolved in 18r.1.00aa, 18r.1.00b, and 18r.2.00 under the defect records DEFECT000668955, SLXOS-25962, and SLXOS-37390. All three defect IDs refer to the same defect and fix.
There is no workaround. This issue can be observed even when control protocols such as LLDP and LACP are disabled.
Release notes list MPLS and VPLS as aspects of the defect. They are characteristics of the specific environment where the issue was discovered. The issue can occur even without MPLS/VPLS.
The error rate is on the order of 1 CRC error every 4 million packets, so the degree of effect prior to upgrading software can be considered extremely low.