How expiring secret links work
Expiration limits how long Strumio will make an encrypted payload available. It narrows the retrieval window, but it cannot revoke plaintext that a viewer already copied or make the underlying credential expire.
By Strumio Editorial Team · Published August 28, 2026 · Updated August 28, 2026
Understand what expires
Strumio encrypts message and file content in the sender's browser and stores ciphertext for delivery. A configured expiration tells the service when that item should no longer be retrievable through the normal link flow. Short retention reduces the time available to someone who later discovers the complete URL.
The URL fragment containing key material is not a remote kill switch, and expiration does not reach plaintext already displayed or downloaded. It also does not disable a password, API key, invitation, recovery code, or document described by the message. Revoke those capabilities in their source systems when they should stop working.
Choose a lifetime based on recipient readiness
Coordinate before creating a very short-lived item. Consider time zones, work schedules, travel, accessibility, and the possibility of a failed first attempt. A window that is too short encourages unsafe resending and duplication; one that is unnecessarily long expands the opportunity for accidental forwarding or device compromise.
Use one-time access when exactly one retrieval is appropriate and the recipient is prepared. Use a short multi-access window when preview, download, or another device may be necessary. Add a separately delivered password for an independent barrier, but do not use longer retention merely because a password exists.
Protect the complete link while active
The complete link is sensitive because its fragment carries decryption key material. Send it directly to a verified recipient and avoid public posts, shared documents, support tickets, URL shorteners, and analytics systems. A locally generated QR code contains the same complete link and needs equivalent protection.
Verify unusual requests through a known channel. Browser encryption protects content within the designed flow, not a compromised sender or recipient device. Extensions, malware, screen recording, synchronized clipboards, and intentional forwarding can expose plaintext or the active capability.
Plan for failed, early, and wrong-person access
Tell the recipient what to expect and confirm completion using non-sensitive details. If a link expires before legitimate access, create a new item rather than extending assumptions around the old one. If the wrong person may have opened it, do not rely on subsequent deletion or expiry to undo disclosure.
Rotate the underlying credential, cancel invitations, invalidate sessions, or replace exposed codes promptly. Review where the link was sent and remove accidental copies where possible. One-time consumption proves only that one retrieval succeeded; it does not establish the first viewer's human identity.
Close the delivery lifecycle
Delete an active item early when its delivery purpose is complete, and retain only the operational record your policy requires without the plaintext or full link. Recipients should move authorized long-term material into an approved password manager, secret store, or records system and remove unnecessary download copies.
Expiring links work best for focused handoffs. For recurring collaboration, use individually attributable accounts and systems that support revocation, audit, versioning, retention, and recovery. Expiration is a useful exposure-reduction control, not a guarantee of secrecy after disclosure.
Related guidance
When an encrypted delivery link is appropriate, Create a free Strumio account.