  Camera sensor noise is one of the most reliable device characteristics in
digital image forensics, enabling the unique linkage of images to digital
cameras. This so-called camera fingerprint gives rise to different
applications, such as image forensics and authentication. However, if images
are publicly available, an adversary can estimate the fingerprint from her
victim and plant it into spurious images. The concept of fragile camera
fingerprints addresses this attack by exploiting asymmetries in data access:
While the camera owner will always have access to a full fingerprint from
uncompressed images, the adversary has typically access to compressed images
and thus only to a truncated fingerprint. The security of this defense,
however, has not been systematically explored yet. This paper provides the
first comprehensive analysis of fragile camera fingerprints under attack. A
series of theoretical and practical tests demonstrate that fragile camera
fingerprints allow a reliable device identification for common compression
levels in an adversarial environment.
