Continuous Discovery of Vulnerabilities in LLM Serving Systems with Fuzzing
On the map: Efficient LLM inference and serving → Serving systems and request scheduling
Abstract (arXiv)
LLM inference and serving systems have become security-critical infrastructure; however, many of their most concerning failures arise from the serving layer rather than from model behavior alone. Modern inference engines combine KV cache, batching, prefix sharing, speculative decoding, adapters, and multi-tenant scheduling, creating shared-state behavior that only emerges under realistic concurrent workloads and is missed by standard model, safety, and API tests. We present GRIEF, a greybox fuzzer for LLM inference engines that treats timed multi-request traces as first-class inputs, uses lightweight oracles to detect crashes, hangs, performance pathologies, and silent output corruption, and applies controlled replay with log-probability checks to confirm reproducible serving-layer failures. Across early campaigns on vLLM and SGLang, GRIEF discovers 15 vulnerabilities, 10 confirmed by engine developers, including 2 CVEs, spanning KV-cache isolation failures, cross-request performance interference, and crash or liveness bugs. These results show that concurrency, caching, and state reuse can induce silent cross-request contamination, noisy-neighbor denial of service, and delayed crashes without malformed inputs or explicit server errors, making concurrent serving behavior a first-class security and reliability boundary for LLM infrastructure.
Key facts. Cited by 1 paper in the map (data through 7 Oct 2026). Placed in Serving systems and request scheduling, one of 12 directions in Efficient LLM inference and serving. Builds on 24 of its 35 references that are in the map. First posted on arXiv 11 May 2026.
Builds on
24 of 35 references.
References · 24
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12 more
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Built on by
Citing papers per year: 2026: 1.
1 paper.
Similar, not cited
Close in wording, no citation either way
- 2026GhostServe: A Lightweight Checkpointing System in the Shadow for Fault-Tolerant LLM Serving
- 2026SeedSmith: LLM-Driven Seed Synthesis for Directed Fuzzing ↗
- 2026Antaeus: Hunting Repository-Level Logic Vulnerabilities via Context-Grounded LLM Reasoning ↗
- 2026FailureAtlas: A Taxonomy of Failure Modes in Multi-Provider LLM Serving Infrastructure
- 2026Concordia: JIT-Compiled Persistent-Kernel Checkpointing for Fault-Tolerant LLM Inference
- 2026Governing the KV Cache: Preventing Timing Side-Channel Leakage in Multi-Tenant LLM Inference
- 2026ChainFuzzer: Greybox Fuzzing for Workflow-Level Multi-Tool Vulnerabilities in LLM Agents
- 2026Rethinking Latency Denial-of-Service: Attacking the LLM Serving Framework, Not the Model