TYPO3 Core

after the last patchupdates (7.6.42-7.6.43) i got an exception on pages where the standard typo3 forms are in use. (i got the same error in another project with 8.7.34 too)

#1588784142: Cannot unserialize TYPO3\CMS\Core\Log\Writer\AbstractWriter
BadMethodCallException thrown in file
/html/typo3/typo3_src-7.6.43/typo3/sysext/core/Classes/Security/BlockSerializationTrait.php in line 32.

full error is in the image attachement...

the form itself:

enctype = multipart/form-data
method = post
prefix = tx_form
confirmation = 
postProcessor {
    1 = mail
    1 {
        recipientEmail = <censored>
        senderEmail = <censored>
        subject = Nachricht via Kontakformular auf <censored>
    }
    2 = redirect
    2 {
        destination = 7
    }
}
10 = TEXTLINE
10 {
    type = text
    name = name
    label {
        value = Name
    }
}
20 = TEXTLINE
20 {
    type = text
    name = email
    label {
        value = E-Mail
    }
}
30 = TEXTAREA
30 {
    cols = 40
    rows = 5
    class = form-control
    name = message
    label {
        value = Nachricht
    }
}
40 = SUBMIT
40 {
    type = submit
    class = btn btn-primary
    name = 5
    value = Formular absenden
}
rules {
    1 = email
    1 {
        breakOnError = 0
        showMessage = 
        message = (max.muster@domain.com)
        error = Dies ist keine gültige E-Mail-Adresse
        element = email
    }
}