Whether you're heading out for a well-deserved summer vacation or just a few days of rest in the fall, setting up an out-of-office (OOO) reply is usually one of the last tasks on your list. More often than not, it's done in a rush.
But have you ever considered that this automated response could be a goldmine for hackers? Even a simple OOO message can reveal a surprising amount of information: who is unavailable, for how long, and who is covering for them. These details are exactly what attackers need for successful phishing or social engineering campaigns against your organization.
Out-of-Office = Out-of-Security?
Cyberattacks are becoming increasingly personalized and targeted. Attackers are constantly looking for small details they can exploit to craft convincing phishing emails or social engineering schemes. Out-of-office replies are often a goldmine of information.
The issue isn’t the automatic reply itself, but how it’s written.
Here's an example of what not to do:
“I'll be out of the office until August 15th, without access to email. For urgent matters, please contact my colleague at: sofie.janssens@bedrijf.be. I'm on vacation in Italy 🌞 – you'll hear from me after August 20th!"
This short message gives potential attackers more than enough to work with:
- They know who is currently unavailable.
- They can target the replacement with fake urgent requests, e.g., "Sofie, I'm writing to you because an urgent payment is still outstanding."
- They can send spear phishing-mails once you're back in the office, e.g., “Welcome back! Here are your invoices from last month.”
What can you do better?
5 smart tips for a secure out-of-office reply
Now you’re probably wondering: How do I write an out-of-office message the right way?
Below are five practical tips to help you reduce the risk of exposing sensitive information when setting up your next OOO message:
1. Keep It Professional and Vague
Let people know you're out, but avoid sharing specific dates, locations or other details. For example:
"Thank you for your message. I’m currently away and will respond to your email as soon as possible after my return."
2. Use a Generic Email Address as a Backup Contact
You don’t want to leave customers or external contacts without support, but you also shouldn’t expose colleagues to potential phishing attempts. Instead of sharing someone’s full name and email address, use a generic contact like support@company.com or info@company.com. This approach maintains accessibility while limiting personal exposure..
"Thank you for your message. I am currently away and will respond to your email as soon as possible after my return.
For urgent matters, please contact our team at support@axsguard.com."
3. Avoid Personal Information
Don’t mention holiday destinations, mobile phone numbers or any personal details. An out-of-office reply is not the place for emojis, photos or updates about your vacation. That content belongs on your social media, not in an automated email.
4. Build a 'Human Firewall' for your organisation
Technology alone can't protect you. The most powerful first line of defense is your team, acting as a human firewall. By providing regular security awareness training , you empower employees to recognize and respond to phishing and social engineering tactics, turning them from potential targets into vigilant protectors of your organization.
5. Inform Your Team
Don't forget to tell your colleagues when you'll be away. This simple step creates a crucial internal safeguard. If your teammates receive a suspicious message that appears to be from you, they'll know to be on high alert and spot the red flags. While it may seem obvious, this simple practice is often overlooked in larger organizations and is an essential part of a comprehensive security strategy.
Out-of-Office Replies: A Hidden Cybersecurity Threat?