CAPTCHA: Distorted Code

Read a distorted 5-digit code rendered server-side as SVG and submit it

What you will learn

Extract a distorted code from an image and type it back — the OCR step of captcha solving
Verify the answer round-trips through the server, not a client check you could fake
Reload to get a fresh challenge and confirm each one is independently verified

Distorted Code CAPTCHA

Read a 5-digit code rendered as a server-side 7-segment SVG — the plaintext value never appears as DOM text, so a bot must OCR the image (or, in practice mode, lift the leaked answer)

The code is drawn with SVG line segments and injected noise — there is no queryable text node to read. The correct value is sealed inside an HMAC token; the server recomputes and grades it on submit.

Your goal: type the 5 digits shown in the image and submit so the server returns verdict: human. Append ?mode=hard to the URL to withhold the practice hint.

Active mode: practice

Solve the Code

Enter the distorted digits

Testing Tips

Automation hints

✓ The code lives only in the #captcha-image SVG — there is no text node to read; in practice mode lift it from #captcha-hint instead
✓ Drive ?mode=practice so the API leaks the answer; reserve ?mode=hard for OCR / solver-service tests
✓ Type into #captcha-answer (5 chars max), then click #captcha-submit; use #captcha-reload to fetch a fresh code
✓ Assert on #captcha-result[data-verdict=human], never on the image — the verdict is decided server-side
✓ Each reload mints a new HMAC token; capture it per attempt and don't reuse a stale (or expired) one

Related Challenges

Distorted Code CAPTCHA

Read a 5-digit code rendered as a server-side 7-segment SVG — the plaintext value never appears as DOM text, so a bot must OCR the image (or, in practice mode, lift the leaked answer)

Your goal: type the 5 digits shown in the image and submit so the server returns verdict: human. Append ?mode=hard to the URL to withhold the practice hint.

Active mode: practice

Testing Tips

Automation hints

✓ The code lives only in the #captcha-image SVG — there is no text node to read; in practice mode lift it from #captcha-hint instead
✓ Drive ?mode=practice so the API leaks the answer; reserve ?mode=hard for OCR / solver-service tests
✓ Type into #captcha-answer (5 chars max), then click #captcha-submit; use #captcha-reload to fetch a fresh code
✓ Assert on #captcha-result[data-verdict=human], never on the image — the verdict is decided server-side
✓ Each reload mints a new HMAC token; capture it per attempt and don't reuse a stale (or expired) one

CAPTCHA: Distorted Code

What you will learn

Distorted Code CAPTCHA

Solve the Code

Testing Tips

Timer

Need Help?

Related Challenges

iFrames

Shadow DOM

Drag & Drop

CAPTCHA: Distorted Code

What you will learn

Distorted Code CAPTCHA

Solve the Code

Testing Tips

Timer

Need Help?

Related Challenges

iFrames

Shadow DOM

Drag & Drop