Developers share terminal screenshots constantly. Stack Overflow answers, GitHub issue reports, Slack messages to teammates, blog posts, conference talks — the terminal window is as common a communication tool as plain text. And almost every developer has, at some point, shared one without noticing what was lurking just above the visible frame, or right there in plain sight.
API keys, bearer tokens, database connection strings, the contents of .env files, private hostnames, AWS credentials — these end up in terminal screenshots more often than most developers realize. The consequences range from embarrassing to catastrophic. This guide walks through what to look for, what can go wrong, and how to stop it from happening.
Before you hit Cmd+Shift+4, consider what your terminal window actually contains. Here are the most common categories of sensitive data that end up in shared screenshots:
aws configure list, check environment variables, or debug IAM issues. The format AKIA... is immediately recognizable to bots that scan GitHub and Pastebin.postgresql://user:password@host:5432/dbname or mongodb+srv://... appear frequently when debugging connection issues.cat .env, env | grep API, or accidentally echoing environment variables mid-session.git log output.Terminal history is also a silent threat. When you scroll up to show context for a question, you may be exposing commands run hours ago in the same session.
The severity of a leaked secret in a terminal screenshot depends on what it unlocks, but the consequences are reliably bad.
AWS bill shock is the most documented outcome. Automated bots continuously scan GitHub commits, public Gists, Stack Overflow posts, and Pastebin for AWS key patterns. When a key is found, it is used within minutes — not hours — to spin up GPU instances for cryptocurrency mining or to exfiltrate data from S3 buckets. Developers have reported bills of $50,000 or more appearing overnight after an accidental key exposure. AWS will sometimes waive these charges for first-time incidents, but there is no guarantee, and the process takes weeks.
Compromised databases are the second most common outcome. A connection string with valid credentials gives an attacker direct access to production data. In regulated industries, a single database exposure can trigger mandatory breach notifications, audits, and fines under GDPR or HIPAA.
Cascading access is what makes API token leaks particularly dangerous. A single leaked token for a third-party service can expose not just that service but anything it integrates with — payment processors, email platforms, customer data stores. Tokens that appear to have limited scope often have more access than their names suggest.
The pattern in most of these incidents is the same: a developer shares a screenshot to get help with a technical problem, the secret is visible but not noticed, the image is indexed or cached, and automated systems find it before anyone thinks to rotate the credential.
If you do not have automated tooling in place, manual review is your fallback. It is imperfect, but it is better than nothing.
Scroll up before you capture. Before taking the screenshot, scroll through the visible terminal history. Look for any commands that output credentials, any environment variable echoes, any API calls with tokens in the URL or headers. Close the terminal tab and open a fresh one if you are not sure.
Crop aggressively. Use macOS's built-in screenshot tools (Cmd+Shift+4 for a selection) to capture only the exact region you need to share. Do not capture the full terminal window if only two lines are relevant.
Redact in Preview or another image editor. Open the screenshot in Preview, use the markup tools to draw filled rectangles over any sensitive values, and flatten the image before sharing. Be careful: drawing a shape over text in some tools leaves the underlying pixels intact under a transparent layer. Make sure the redaction is actually opaque. For more on proper redaction technique, see how to blur text in screenshots on macOS.
The problem with manual review is that it requires you to correctly identify every sensitive value every time, under the time pressure of a live debugging session. Secrets do not always look like secrets at a glance. A long hexadecimal string might be a commit hash, a session ID, or a production API key — and telling the difference requires context you may not have in the moment.
BlurData is a macOS app that automatically detects and blurs sensitive data in screenshots. It works entirely offline — your images never leave your Mac — which makes it appropriate for work involving confidential infrastructure.
Here is how to use it for terminal screenshots:
The detection engine covers the patterns that appear most often in terminal output: AWS key formats, common API token structures, JWT strings, connection string formats, email addresses, IP addresses, and more. You can also define custom regex patterns if your team uses internal credential formats that do not match standard patterns.
BlurData costs $29 as a one-time purchase and requires macOS. There is no subscription.
The best time to prevent a leaked secret is before the screenshot is taken. A few habits make a significant difference:
clear removes visible history from the current view. This does not delete shell history, but it prevents accidental inclusion of earlier commands in a screenshot.YOUR_API_KEY_HERE or sk-xxxxxxxxxxxx before taking the screenshot. Do not blur a real key — replace it at the source.Everything above applies equally to IDE screenshots. VS Code, JetBrains IDEs, and other editors show the same terminal panels, and they add additional exposure vectors:
Open file tabs visible in the tab bar can reveal file paths, including paths to credential files like .env, credentials.json, or config/secrets.yml. Even if the file content is not visible, the path tells an attacker where to look.
Inline variable values shown by debuggers, hover tooltips, or watch panels can include live credential values if you are stepping through code that handles authentication.
Terminal output in the integrated terminal carries exactly the same risks as a standalone terminal. Developers often forget that the IDE terminal has the same environment and history as any other shell session.
Git panels showing recent commit messages, diff views, or blame annotations can reveal commit messages or changes that reference credentials — especially if someone previously hard-coded a secret and then removed it.
The same workflow applies: crop to the minimum necessary region, use BlurData to auto-detect sensitive values before sharing, and develop the habit of reviewing what is visible before the screenshot is taken.
Terminal screenshots are a normal and useful part of developer communication. The goal is not to stop sharing them — it is to share them without accidentally handing over the keys to your infrastructure.
The combination of deliberate pre-screenshot habits and automated detection covers the cases that manual review misses. Most credential leaks in screenshots are not caused by carelessness in the abstract — they are caused by a busy developer focusing on the technical problem in front of them and not noticing what else is in the frame.
Building a step into your workflow where a tool checks the image before it leaves your machine is the most reliable way to close that gap. Download BlurData and make it part of your screenshot workflow — it takes seconds per image and costs nothing in the moment it matters.