Skip to Main content Skip to Navigation
Conference papers

Forgetting the Forgotten with Lethe: Conceal Content Deletion from Persistent Observers

Abstract : Most social platforms offer mechanisms allowing users to delete their posts, and a significant fraction of users exercise this right to be forgotten. However, ironically, users' attempt to reduce attention to sensitive posts via deletion, in practice, attracts unwanted attention from stalkers specifically to those (deleted) posts. Thus, deletions may leave users more vulnerable to attacks on their privacy in general. Users hoping to make their posts forgotten face a "damned if I do, damned if I don't" dilemma. Many are shifting towards ephemeral social platform like Snapchat, which will deprive us of important user-data archival. In the form of intermittent withdrawals, we present, Lethe, a novel solution to this problem of (really) forgetting the forgotten. If the next-generation social platforms are willing to give up the uninterrupted availability of non-deleted posts by a very small fraction, Lethe provides privacy to the deleted posts over long durations. In presence of Lethe, an adversarial observer becomes unsure if some posts are permanently deleted or just temporarily withdrawn by Lethe; at the same time, the adversarial observer is overwhelmed by a large number of falsely flagged un-deleted posts. To demonstrate the feasibility and performance of Lethe, we analyze large-scale real data about users' deletion over Twitter and thoroughly investigate how to choose time duration distributions for alternating between temporary withdrawals and resurrections of non-deleted posts. We find a favorable trade-off between privacy, availability and adversarial overhead in different settings for users exercising their right to delete. We show that, even against an ultimate adversary with an uninterrupted access to the entire platform, Lethe offers deletion privacy for up to 3 months from the time of deletion, while maintaining content availability as high as 95% and keeping the adversarial precision to 20%.
Document type :
Conference papers
Complete list of metadatas

Cited literature [42 references]  Display  Hide  Download
Contributor : Patrick Loiseau <>
Submitted on : Tuesday, December 18, 2018 - 2:52:01 PM
Last modification on : Friday, July 3, 2020 - 4:52:47 PM
Document(s) archivé(s) le : Wednesday, March 20, 2019 - 11:55:31 AM


Files produced by the author(s)


  • HAL Id : hal-01959119, version 1



Mohsen Minaei, Mainack Mondal, Patrick Loiseau, Krishna Gummadi, Aniket Kate. Forgetting the Forgotten with Lethe: Conceal Content Deletion from Persistent Observers. PETS 2019 - 19th Privacy Enhancing Technologies Symposium, Jul 2019, Stockholm, Sweden. pp.1-21. ⟨hal-01959119⟩



Record views


Files downloads