I successfully resolved a similar issue where I needed to redact all the tokens in my logs. Thanks to @zamentali's answer, I used a regex, and it worked perfectly:

processors:
  transform/redact_sensitive_info:
    error_mode: ignore
    log_statements:
    - context: log
      statements:
      - replace_pattern(body, "token\\=[^\\s]*(\\s?)", "token=REDACTED")
      - replace_pattern(attributes["message"], "token\\=[^\\s]*(\\s?)", "token=REDACTED")

service:
  pipelines:
    logs:
      receivers: [xyz]
      processors: [transform/redact_sensitive_info, xyz]
      exporters: [xyz]