[Question] Lack of trustworthy in vote signature in light clients

[hyunsooda]

Hi team,

I've observed that validators sign a vote header, which differs from the standard header by excluding certain fields like AppHash. Thus, AppHash isn't included in the validator-signed fields.

Given the light client's inability to replay transactions to calculate AppHash, I assumed this critical value would be part of the vote header's signed fields. However, it appears not to be included, raising concerns about the potential ease of forging the AppHash field by modifying this value alone. Could someone clarify this issue for me? Thanks!