Web Cache Overflow: Exploiting Imprecise Keys for Cache Degradation and Beyond

• URL: http://arxiv.org/abs/2608.04744v1
• Date: Wed, 05 Aug 2026 12:12:33 GMT
• Title: Web Cache Overflow: Exploiting Imprecise Keys for Cache Degradation and Beyond
• Abstract summary: We show that request elements included unnecessarily in cache keys can be abused to create redundant cache entries.<n>In susceptible deployments, sustained generation of such redundant copies reduces cache effectiveness and increases origin load.<n>We conclude that precise cache-key design is the most direct mitigation against this abuse vector and should be recognized as a security best practice.
• Score: 3.374749757360864
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: Web caches support the scalability needs of contemporary web applications by storing frequently accessed objects closer to clients. Web caches are conceptually associative arrays, tracking stored objects using cache keys consisting of HTTP request fields. However, these cache keys are often imprecisely defined by website operators. This allows clients to craft a multitude of requests that target the same object, but map to different cache keys. In this work, we show that request elements included unnecessarily in cache keys can be abused to create redundant cache entries. In susceptible deployments, sustained generation of such redundant copies reduces cache effectiveness and increases origin load, facilitating eviction-dependent attacks. Our experiments reproduce cache degradation across five stand-alone caching proxies and characterize how these parameters affect attacker cost and cache hit rate, potentially resulting in denial-of-service attacks. We conclude that precise cache-key design is the most direct mitigation against this abuse vector and should be recognized as a security best practice.

Related papers

• LaCache: Robust Semantic Caching for LLM Serving [10.741523413040559]
  We present LaCache, a novel semantic caching scheme that addresses cache-collision attacks.<n>LaCache checks the cache hit of its first k decoded tokens rather than checking only the cache hit of a query.<n>We prove that it is impossible to craft adversarial queries that simultaneously elicit malicious responses and collide with benign queries.
  arXiv  Detail & Related papers  (2026-08-03T05:31:24Z)
• Back from the Future: Key-Value Cache Management by Counter-Causal Surprise [67.1056509495879]
  Key-value (KV) cache management through compression and eviction strategies has emerged as an important research direction in recent years.<n>We propose a simple yet effective KV eviction scheme motivated by the insight that past tokens which can be well-predicted from more recent tokens are redundant.<n>We evaluate our strategy on various open-source LLMs and benchmark datasets showing competitive or improved performance over other state-of-the-art methods.
  arXiv  Detail & Related papers  (2026-07-30T02:42:51Z)
• Decouple and Cache: KV Cache Construction for Streaming Video Understanding [53.55135022958052]
  Streaming video understanding requires processing unbounded video streams with limited memory and computation.<n>We propose Decoupled Streaming Cache(DSCache), a training-free cache construction mechanism that adapts pretrained offline models to streaming settings.<n> Experiments on Streaming Video QA benchmarks demonstrate DSCache's state-of-the-art performance, with an average 2.5% accuracy gains over prior methods.
  arXiv  Detail & Related papers  (2026-05-03T13:02:44Z)
• SenCache: Accelerating Diffusion Model Inference via Sensitivity-Aware Caching [75.02865981328509]
  Caching reduces computation by reusing previously computed model outputs across timesteps.<n>We propose Sensitivity-Aware Caching (SenCache), a dynamic caching policy that adaptively selects caching timesteps on a per-sample basis.<n>SenCache achieves better visual quality than existing caching methods under similar computational budgets.
  arXiv  Detail & Related papers  (2026-02-27T17:36:09Z)
• Breaking Diffusion with Cache: Exploiting Approximate Caches in Diffusion Models [1.399348653165494]
  We introduce a prompt stealing attack using the cache, where an attacker can recover existing cached prompts based on cache hit prompts.<n>We introduce a poisoning attack that embeds the attacker's logos into the previously stolen prompt, to render them in future user prompts that hit the cache.<n>These attacks are all performed remotely through the serving system, which indicates severe security vulnerabilities in approximate caching.
  arXiv  Detail & Related papers  (2025-08-28T04:46:44Z)
• vCache: Verified Semantic Prompt Caching [95.16654660556975]
  This paper proposes vCache, the first verified semantic cache with user-defined error rate guarantees.<n>It employs an online learning algorithm to estimate an optimal threshold for each cached prompt, enabling reliable cache responses without additional training.<n>Our experiments show that vCache consistently meets the specified error bounds while outperforming state-of-the-art static-threshold and fine-tuned embedding baselines.
  arXiv  Detail & Related papers  (2025-02-06T04:16:20Z)
• Efficient Inference of Vision Instruction-Following Models with Elastic Cache [76.44955111634545]
  We introduce Elastic Cache, a novel strategy for efficient deployment of instruction-following large vision-language models. We propose an importance-driven cache merging strategy to prune redundancy caches. For instruction encoding, we utilize the frequency to evaluate the importance of caches. Results on a range of LVLMs demonstrate that Elastic Cache not only boosts efficiency but also notably outperforms existing pruning methods in language generation.
  arXiv  Detail & Related papers  (2024-07-25T15:29:05Z)
• Hidden Web Caches Discovery [3.9272151228741716]
  This paper presents a novel methodology for cache detection using timing analysis. Our approach eliminates the dependency on cache status headers, making it applicable to any web server.
  arXiv  Detail & Related papers  (2024-07-23T08:58:06Z)
• CacheSquash: Making caches speculation-aware [11.499924192220274]
  Speculation is key to achieving high CPU performance, yet it enables risks like Spectre attacks.<n>We propose a novel mitigation, CacheSquash, that cancels mis-speculated memory accesses.<n>We implement CacheSquash on gem5 and show that it thwarts practical Spectre attacks, with near-zero performance overheads.
  arXiv  Detail & Related papers  (2024-06-17T21:43:39Z)
• Systematic Evaluation of Randomized Cache Designs against Cache Occupancy [11.018866935621045]
  This work fills in a crucial gap in current literature on randomized caches.<n>Most randomized cache designs defend only contention-based attacks, and leave out considerations of cache occupancy.<n>Our results establish the need to also consider cache occupancy side-channel in randomized cache design considerations.
  arXiv  Detail & Related papers  (2023-10-08T14:06:06Z)
• BackCache: Mitigating Contention-Based Cache Timing Attacks by Hiding Cache Line Evictions [7.46215723037597]
  L1 data cache attacks pose a significant privacy and confidentiality threat. BackCache always achieves cache hits instead of cache misses to mitigate contention-based cache timing attacks on the L1 data cache. BackCache places the evicted cache lines from the L1 data cache into a fully-associative backup cache to hide the evictions.
  arXiv  Detail & Related papers  (2023-04-20T12:47:11Z)
• Reinforcement Learning for Caching with Space-Time Popularity Dynamics [61.55827760294755]
  caching is envisioned to play a critical role in next-generation networks. To intelligently prefetch and store contents, a cache node should be able to learn what and when to cache. This chapter presents a versatile reinforcement learning based approach for near-optimal caching policy design.
  arXiv  Detail & Related papers  (2020-05-19T01:23:51Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.