Check all installed certificate against Let's Encrypt CAA problem - see https://letsencrypt.org/caaproblem/

check-caa.sh

#!/bin/sh

set -e

SERIALURI=https://d4twhgtvn0ff5.cloudfront.net/caa-rechecking-incident-affected-serials.txt.gz
SERIALTMPFILE=/tmp/caa-rechecking-incident-affected-serials.txt

download_serials() {
    curl "$SERIALURI" | gunzip | awk '{print $2}' > "$SERIALTMPFILE"
}

# EFF's Certbot
certbot_list_certificates() {
    if command -v certbot 1>/dev/null 2>&1; then
        certbot certificates 2>/dev/null | \
            awk -F: '/Certificate Path/ {sub(/fullchain\.pem$/, "cert.pem", $2); print $2}'
    fi
}

# OpenBSD's acme-client
acme_client_list_certificates() {
    if command -v acme-client 1>/dev/null 2>&1; then
        acme-client -n 2>/dev/null | grep 'domain certificate' | cut -d \" -f 2
    fi
}

list_all_certificates() {
    certbot_list_certificates
    acme_client_list_certificates
}

print_serial() {
    openssl x509 -noout -serial | awk '{sub(/^serial=/, "", $0); print tolower($0)}'
}

test -f "$SERIALTMPFILE" || download_serials
list_all_certificates | while read cert; do
    serial=$(cat $cert | print_serial)
    if grep "$serial" "$SERIALTMPFILE" >/dev/null; then
        echo "${cert} is affected."
    fi
done

MIT Licensed, if your computer burns because of this script it's not my fault.

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.