PS21. User-data Corruption (derived from original P4. PDU Corruption/Loss Pattern)

Initial publication	W. Mazurczyk, S. Wendzel, K. Cabaj in [3]. However, this pattern is based on the original P4. PDU Corruption/Loss Pattern, which was introduced by S. Wendzel, S. Zander, B. Fechner, C. Herdin in [1]. The pattern P4 was split up into two separate patterns (the  Frame Collisions pattern and Artificial Loss pattern), cf. [2]. P4 was later also re-introduced for user-data as PS21. User-data Corruption, cf. [3].
Illustration	This pattern is related to the cases when steganographic methods do not take into account what kind of user-data is carried within a payload field and/or what its characteristic is (blind modification). It can be applied to single PDUs or to multiple PDUs (a flow). This typically happens if parts of (or the whole) user-data is replaced with secret bits and thus the user-data is corrupted/lost.
Context	Network Covert Channel Patterns → Covert Storage Channel Patterns → Modification of Payload → User-data Agnostic
Evidence	see [3].
Implementation

References:
[1] S. Wendzel, S. Zander, B. Fechner, C. Herdin: Pattern-based Survey and Categorization of Network Covert Channel Techniques, ACM Computing Surveys, Vol. 47, Issue 3, pp. 50:1-26, ACM, 2015.
An early version of the article is available here: download.

[2] W. Mazurczyk, S. Wendzel, S. Zander, A. Houmansadr, K. Szczypiorski: Information Hiding in Communication Networks, Wiley, 2016. Chapters 3 and 8 contain discussions on hiding patterns, basically on the basis of [1] but with an extension of timing-based patterns.

[3] W. Mazurczyk, S. Wendzel, K. Cabaj: Towards Deriving Insights into Data Hiding Methods Using Pattern-based Approach, in Proc. Second International Workshop on Criminal Use of Information Hiding (CUING 2018) at ARES, pp. 10:1-10:10, ACM, 2018.