~/talk

From Purity to Peril: Backdooring Merged Models From "Harmless" Benign...

Talkat USENIX Security '25 · 2025-08-13..08-15· [security, machine-learning]
links:none on file
links:none on file
links:none on file
name:Xinlei He
links:none on file
name:Zhan Qin
links:none on file
links:none on file
slides:none on file

Introduces MergeBackdoor, a two-stage training method that makes each upstream model appear clean (upstream ASRs at random-guessing level) yet causes the merged model to exhibit a backdoor with ASR ≈ 1.0. Demonstrates across ViT, BERT and LLM families on 12 datasets and multiple merging schemes, shows batch-by-batch updating is critical for convergence, locates key vulnerable middle layers, preserves clean accuracy, and finds existing detectors—even those aware of triggers—fail to flag the upstream models.

AI-written summary · about

  1. 0:00Model merging vulnerabilities
  2. 2:42Beer and sewage reaction
  3. 3:47Emergent backdoors
  4. 5:12Merge Backdoor training
  5. 7:22Batch updating role
  6. 8:28Evaluating Merge Backdoor
  7. 9:59Effectiveness vs clean accuracy
  8. 10:41Merge Backdoor robustness
  9. 11:22Multimodel merging attack
  10. 12:48Backdoor propagation layers
  11. 14:15Detection challenges
~/search
type to search 6,249 conferences, 138,987 speakers and 185,172 talks
~/help
cmdctrl k
search every conference, speaker and series
/
focus the filter search
h
home
c
conferences
s
speakers
e
series
t
light / dark — the status bar button does the same
?
this help
esc
close this, then clear every filter — or just the search, while you are typing in it

Ignored while you are typing. Pages without a filter rail have no search to focus.