#pseudonymity — Public Fediverse posts

Large-scale online deanonymization with LLMs
From Cornel University Computer Science

We show that large language models can be used to perform at-scale deanonymization. With full Internet access, our agent can re-identify Hacker News users and Anthropic Interviewer participants at high precision, given pseudonymous online profiles and conversations alone, matching what would take hours for a dedicated human investigator. We then design attacks for the closed-world setting. Given two databases of pseudonymous individuals, each containing unstructured text written by or about that individual, we implement a scalable attack pipeline that uses LLMs to: (1) extract identity-relevant features, (2) search for candidate matches via semantic embeddings, and (3) reason over top candidates to verify matches and reduce false positives. Compared to classical deanonymization work (e.g., on the Netflix prize) that required structured data, our approach works directly on raw user content across arbitrary platforms. We construct three datasets with known ground-truth data to evaluate our attacks. The first links Hacker News to LinkedIn profiles, using cross-platform references that appear in the profiles. Our second dataset matches users across Reddit movie discussion communities; and the third splits a single user's Reddit history in time to create two pseudonymous profiles to be matched. In each setting, LLM-based methods substantially outperform classical baselines, achieving up to 68% recall at 90% precision compared to near 0% for the best non-LLM method. Our results show that the practical obscurity protecting pseudonymous users online no longer holds and that threat models for online privacy need to be reconsidered.

Simon Lermen, Daniel Paleka, Joshua Swanson, Michael Aerni, Nicholas Carlini, Florian Tramè

https://arxiv.org/abs/2602

#computerscience #cornelluniversity #AiResearch #privacy #anonymity #llm #HackNews #athropic #pseudonymity
#deanonymization

You've got nothing to hide, do you?

»We show that large language models can be used to perform at-scale #deanonymization. With full Internet access, our agent can re-identify Hacker News users and Anthropic Interviewer participants at high precision, given pseudonymous online profiles and conversations alone, matching what would take hours for a dedicated human investigator. We then design attacks for the closed-world setting. Given two databases of pseudonymous individuals, each containing unstructured text written by or about that individual, we implement a scalable attack pipeline«

https://arxiv.org/abs/2602.16800

"#AI" #privacy #pseudonymity #anonymity #LLM

New Privacy Guides video 🎞️🪪
by @jw:

Age Verification represents an incredible threat to our privacy.

Not only Age Verification doesn't protect the children, but this could mean the end of protective pseudonymity for everyone if implemented widely.

Watch this excellent video created by Jordan here on PeerTube (based on my article on the same topic): https://neat.tube/w/aR4toTWJpcBZamUdQQpGRu

#PrivacyGuides #Privacy #AgeVerification #DataMinimization #Pseudonymity #PeerTube

@vortex_egg There's a very long and substantial history of people adopting pseudonyms, nicknames, pen names, stage names, nommes de guerre, etc., for any number of reasons.

Some you're no doubt aware of, many you're quite likely not. ("Willy Brandt" was a particular surprise for me.)

https://en.wikipedia.org/wiki/Pseudonym
https://en.wikipedia.org/wiki/List_of_pseudonyms
https://en.wikipedia.org/wiki/List_of_pen_names
https://en.wikipedia.org/wiki/List_of_stage_names
https://en.wikipedia.org/wiki/List_of_pseudonyms_used_in_the_American_Constitutional_debates
https://en.wikipedia.org/wiki/Mononymous_person

#pseydonyms #pseudonymity #pseudonymous #PenNames #StageNames #NommesDeGuerre #Anonymity #Identity