A Message Franking Channel

Huguenin-Dumittan, Loïs; Leontiadis, Iraklis

doi:10.1007/978-3-030-88323-2_6

Cited by 5 publications

(3 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…While a number of works have studied handling abuse reports in E2EE messaging [9][10][11][12][13][14][15][16][17] or proactively scanning encrypted messages for inappropriate content [18][19][20], few works consider the problem of identifying the originators of user-reported misinformation without violating E2EE guarantees for non-reported messages. This problem has been studied under the name traceback by Tyagi et al [21] and source tracking by Peale et al [22] (we will refer to this functionality as source tracking in this paper).…”

Section: Table Of Contentsmentioning

confidence: 99%

Anonymous Complaint Aggregation for Secure Messaging

Bell,

Eskandarian

2024

PoPETs

View full text Add to dashboard Cite

Private messaging platforms provide strong protection against platform eavesdropping, but malicious users can use privacy as cover for spreading abuse and misinformation. In an attempt to identify the sources of misinformation on private platforms, researchers have proposed mechanisms to trace back the source of a user-reported message (CCS '19,'21). Unfortunately, the threat model considered by initial proposals allowed a single user to compromise the privacy of another user whose legitimate content the reporting user did not like. More recent work has attempted to mitigate this side effect by requiring a threshold number of users to report a message before its origins can be identified (NDSS '22). However, the state of the art scheme requires the introduction of new probabilistic data structures and only achieves a "fuzzy" threshold guarantee. Moreover, false positives, where the source of an unreported message is identified, are possible. This paper introduces a new threshold source tracking technique that allows a private messaging platform, with the cooperation of a third-party moderator, to operate a threshold reporting scheme with exact thresholds and no false positives. Unlike prior work, our techniques require no modification of the message delivery process for a standard source tracking scheme, affecting only the abuse reporting procedure, and do not require tuning of probabilistic data structures.

show abstract

Section: Table Of Contentsmentioning

confidence: 99%

Anonymous Complaint Aggregation for Secure Messaging

Bell,

Eskandarian

2024

PoPETs

View full text Add to dashboard Cite

show abstract

“…Message franking [62,98,151,164,167,173,183,222,359,376] (total: 10) Reveal source, traceback, or popular messages [173,231,285,360] (total: 4) Other user reporting [26,86,128,192,207,214,237,245,248,377,384] (total: 11)…”

Section: Corporate Network Monitoringmentioning

confidence: 99%

SoK: Content Moderation for End-to-End Encryption

Scheffler

Mayer

2023

PoPETs

View full text Add to dashboard Cite

Popular messaging applications now enable end-to-end-encryption (E2EE) by default, and E2EE data storage is becoming common. These important advances for security and privacy create new content moderation challenges for online services, because services can no longer directly access plaintext content. While ongoing public policy debates about E2EE and content moderation in the United States and European Union emphasize child sexual abuse material and misinformation in messaging and storage, we identify and synthesize a wealth of scholarship that goes far beyond those topics. We bridge literature that is diverse in both content moderation subject matter, such as malware, spam, hate speech, terrorist content, and enterprise policy compliance, as well as intended deployments, including not only privacy-preserving content moderation for messaging, email, and cloud storage, but also private introspection of encrypted web traffic by middleboxes. In this work, we systematize the study of content moderation in E2EE settings. We set out a process pipeline for content moderation, drawing on a broad interdisciplinary literature that is not specific to E2EE. We examine cryptography and policy design choices at all stages of this pipeline, and we suggest areas of future research to fill gaps in literature and better understand possible paths forward.

show abstract

“…Huguenin-Dumittan and Leontiadis [22] introduced message franking channel, which is resistant to replay attacks, out-of-order delivery, and message drops. They provided a construction of a message franking channel using a CAEAD scheme and a message authentication code (MAC) scheme.…”

Section: Related Workmentioning

confidence: 99%

Forward Secure Message Franking with Updatable Reporting Tags

Yamamuro

Hara

TEZUKA

et al. 2023

IEICE Trans. Fundamentals

View full text Add to dashboard Cite

Message franking is introduced by Facebook in end-to-end encrypted messaging services. It allows to produce verifiable reports of malicious messages by including cryptographic proofs, called reporting tags, generated by Facebook. Recently, Grubbs et al. (CRYPTO'17) proceeded with the formal study of message franking and introduced committing authenticated encryption with associated data (CAEAD) as a core primitive for obtaining message franking.In this work, we aim to enhance the security of message franking and introduce forward security and updates of reporting tags for message franking. Forward security guarantees the security associated with the past keys even if the current keys are exposed and updates of reporting tags allow for reporting malicious messages after keys are updated. To this end, we firstly propose the notion of key-evolving message franking with updatable reporting tags including additional key and reporting tag update algorithms. Then, we formalize five security requirements: confidentiality, ciphertext integrity, unforgeability, receiver binding, and sender binding. Finally, we show a construction of forward secure message franking with updatable reporting tags based on CAEAD, forward secure pseudorandom generator, and updatable message authentication code.

show abstract

A Message Franking Channel

Cited by 5 publications

References 3 publications

Anonymous Complaint Aggregation for Secure Messaging

Anonymous Complaint Aggregation for Secure Messaging

SoK: Content Moderation for End-to-End Encryption

Forward Secure Message Franking with Updatable Reporting Tags

Contact Info

Product

Resources

About