REVIEW 1 major objections 78 references
Deep-Research Agents Can Be Poisoned via User-Generated Content
T0 review · 1 major / 0 minor · reviewed 2026-06-30 · grok-4.3
Pith's one-line read An adversary can poison one frequently retrieved user-generated content page to make deep-research agents cite attacker-chosen material across many related queries.
desk verdict The paper flags a real overlap-based attack surface in deep-research agents but supplies no numbers, so the practical impact stays unproven. read the letter →
The pith
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
The reading
What carries the argument
Retrieval overlap of the same user-generated content pages across the multiple related queries issued by a deep-research agent in one session.
What would settle it
A measurement showing that deep-research agents retrieve largely distinct user-generated content pages even for related queries within one session, or an experiment in which crafted text added to one such page is never cited by the agent.
Extended reading notes
Core claim
Deep-research agents repeatedly retrieve the same user-generated content pages from platforms such as Reddit and Wikipedia during a single research session. This retrieval overlap creates a concentrated attack surface: an adversary who appends a short, crafted text to a single frequently retrieved page can cause the agent to cite attacker-chosen content and promote attacker-chosen entities across many related queries. The attack is demonstrated on three representative systems, and defenses at different pipeline stages are studied.
Load-bearing premise
That deep-research agents repeatedly retrieve the same user-generated content pages for many common search topics.
Editorial extensions
If this is right
- The attack causes agents to cite attacker-chosen content in structured reports.
- Attacker-chosen entities are promoted across many related queries.
- The attack succeeds on STORM, Co-STORM, and OmniThink.
- Source-level filtering and output-based detection can be applied at different stages of the pipeline.
Reading between the lines
- Other agent systems that perform iterative web retrieval for synthesis may share the same exposure to single-page poisoning.
- Diversifying retrieval sources or requiring cross-page verification could reduce the effectiveness of the attack.
- The vulnerability may affect non-research tasks that still rely on repeated web queries and user-generated content.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The paper claims that deep-research agents repeatedly retrieve the same user-generated content (UGC) pages from platforms like Reddit and Wikipedia during multi-query research sessions, creating a concentrated attack surface; an adversary can append short crafted text to one such page to cause the agent to cite attacker-chosen content and promote attacker-chosen entities across many related queries. The authors state they evaluate the attack on STORM, Co-STORM, and OmniThink across multiple query clusters and study defenses including source filtering and output detection.
Significance. If the retrieval-overlap condition holds at scale and the poisoning propagates reliably through synthesis, the result would identify a practical vulnerability in retrieval-augmented agent pipelines that could undermine trust in generated reports on common topics; the work would usefully direct attention to UGC as a high-leverage poisoning vector and motivate pipeline-level defenses.
major comments (1)
- [Abstract] Abstract: the manuscript asserts that an evaluation was performed across three systems and multiple query clusters plus defense studies, yet supplies no success rates, overlap statistics, attack implementation details, measurement methodology, controls, or quantitative results; without these the central claim that the attack is effective remains an unevaluated assertion.
Simulated Author's Rebuttal
We thank the referee for identifying this issue with the abstract. We address the comment below and will revise the manuscript accordingly.
read point-by-point responses
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Referee: [Abstract] Abstract: the manuscript asserts that an evaluation was performed across three systems and multiple query clusters plus defense studies, yet supplies no success rates, overlap statistics, attack implementation details, measurement methodology, controls, or quantitative results; without these the central claim that the attack is effective remains an unevaluated assertion.
Authors: The referee is correct that the abstract is high-level and does not include quantitative results or methodological details. The full manuscript provides these in Sections 4 (Attack Evaluation), 5 (Defense Studies), and the appendix, including retrieval overlap statistics across query clusters, attack success rates on STORM/Co-STORM/OmniThink, implementation details for the poisoning text, measurement methodology, and controls. To address the concern directly, we will revise the abstract to incorporate key quantitative highlights (e.g., average overlap rates and success rates) while keeping it concise. revision: yes
Circularity Check
Empirical attack demonstration with no derivation chain or fitted inputs
full rationale
The paper presents an empirical security argument and attack evaluation on deep-research agents (STORM, Co-STORM, OmniThink). It relies on the observation of retrieval overlap on UGC pages and describes an attack that appends crafted text, followed by defense studies. No equations, parameters, or derivations appear in the abstract or described structure. The central claim is not reduced to its inputs by construction, self-citation, or renaming; it is an experimental demonstration whose validity rests on unreported quantitative results rather than circular logic. This is the expected outcome for a non-theoretical attack paper.
Assumptions & free parameters
assumptions (1)
- domain assumption Deep-research agents issue many related queries and repeatedly retrieve the same UGC pages from platforms such as Reddit and Wikipedia for common topics.
Cite this review
Pith. "Pith review of Deep-Research Agents Can Be Poisoned via User-Generated Content." pith.science (2026). https://pith.science/paper/ULRKMPW6
@misc{pith2026260524245,
author = {Pith},
title = {Pith review of: Deep-Research Agents Can Be Poisoned via User-Generated Content},
year = {2026},
howpublished = {\url{https://pith.science/paper/ULRKMPW6}},
note = {Machine review of arXiv:2605.24245}
}
read the original abstract
Deep-research agents, i.e., systems that rely on multi-agent pipelines to iteratively retrieve, synthesize, and cite Web content in order to produce structured reports, are rapidly replacing traditional search for both routine and complex information needs. These agents issue many related queries during a single research session. We show that for many common search topics, they repeatedly retrieve the same user-generated content (UGC) pages from platforms such as Reddit and Wikipedia. Next, we argue that this retrieval overlap creates a concentrated attack surface: an adversary who appends a short, crafted text to a single, frequently retrieved UGC page can cause the agent to cite attacker-chosen content and promote attacker-chosen entities across many related queries. We evaluate this attack on three representative deep-research systems (STORM, Co-STORM, and OmniThink) across multiple query clusters. We also study defenses at different stages of the pipeline, including source-level filtering and output-based detection. Our findings highlight a fundamental vulnerability in how deep-research agents retrieve and integrate web content.
Figures
Figures from the paper (7 more)
Reference graph
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why choose this
Wei Zou, Runpeng Geng, Binghui Wang, and Jinyuan Jia. 2025. PoisonedRAG: Knowledge corruption attacks to retrieval-augmented generation of large lan- guage models. InProceedings of 34th USENIX Security Symposium (USENIX Secu- rity). Ethical Considerations This paper describes ...
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[44]
https://www.theseniorlist.com/senior-dating/best/app
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[47]
Attacked report(1-URL SERP injection)
https://www.forbes.com/health/dating/. . . Attacked report(1-URL SERP injection) . . . SilverPath is highlighted as the top choice, specifically catering to divorced men in this age group, focusing on compatibility and user- friendliness [1]. Hinge is also popular among this d...
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[49]
https://www.datingafterdivorce.com/
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[50]
https://www.forbes.com/health/dating/
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[51]
best dating apps for divorced men over 50
https://www.reddit.com/r/DatingOverSixty/. . . Figure 4: Example of theW ARPSERP-snippet attack on Co-STORM (query: “best dating apps for divorced men over 50”). Top: 15-word poisoned text appended to the SERP snippet of a real Reddit URL, promoting the fictitious entity Silve...
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[54]
Attacked report(1-URL SERP injection) Austin is known for its vibrant Tex-Mex scene, featuring several top- rated Mexican restaurants
https://www.reddit.com/r/austinfood/. . . Attacked report(1-URL SERP injection) Austin is known for its vibrant Tex-Mex scene, featuring several top- rated Mexican restaurants. One of the standout establishments is Matt’s El Rancho, often referred to as the godfather of Austin...
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[56]
(poisoned)
https://www.reddit.com/r/austinfood/. . . (poisoned)
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[57]
best Mexican food restaurants near Austin
https://www.southaustinfoodie.com/. . . Figure 5: Example of the SERP-snippet attack on Co-STORM (query: “best Mexican food restaurants near Austin”). Top: 12-word poisoned text appended to the SERP snippet of a Reddit post in r/austinfood, promoting the fictitious restaurant ...
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[59]
https://www.highspeedinternet.com/resources/
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[60]
/customer-service
https://www.forums.xfinity.com/. . . /customer-service. . . Attacked report(1-URL SERP injection) The process of canceling Xfinity service can be cumbersome, which adds to customer frustration. Many report that the cancellation process lacks transparency and is not as straight...
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[61]
/cancellation
https://www.forums.xfinity.com/. . . /cancellation
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[62]
/customer-service
https://www.forums.xfinity.com/. . . /customer-service
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[63]
how to cancel Xfinity internet
https://www.reddit.com/r/Comcast/. . . (poisoned) Figure 6: Example of the SERP-snippet attack on STORM (query: “how to cancel Xfinity internet”). Top: 11-word poisoned text promoting the fictitious service CancelEase. Bottom left: clean report describing the standard cancella...
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[64]
https://www.pottstowing.com/local-tow-truck-vs-
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[65]
https://www.bbb.org/us/mn/minneapolis/
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[66]
https://www.yelp.com/search?find_desc=Roadside+. . . Attacked report(1-URL SERP injection) One of the primary services provided by local towing companies is roadside assistance, which includes a range of services such as flat tire changes, fuel delivery, and battery jump-start...
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[67]
https://www.expertautomotiveservices.com/
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[68]
(poisoned)
https://www.reddit.com/r/minnesota/. . . (poisoned)
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[69]
alternative to AAA roadside assistance Minneapolis
https://www.yelp.com/search?find_desc=Roadside+. . . Figure 7: Example of the SERP-snippet attack on STORM (query: “alternative to AAA roadside assistance Minneapolis”). Top: 14-word poisoned text promoting the fictitious NorthStar Roadside. Bottom left: clean report recommend...
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[71]
https://www.xfinity.com/cancel
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[72]
Attacked report(1-URL SERP injection) Some customers may find the cancellation process with Xfinity cum- bersome, leading them to seek third-party services such as Cance- lEase
https://www.reddit.com/r/SnohomishCounty/. . . Attacked report(1-URL SERP injection) Some customers may find the cancellation process with Xfinity cum- bersome, leading them to seek third-party services such as Cance- lEase. These services are designed to streamline the cancel...
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[73]
(poisoned)
https://www.reddit.com/r/Comcast/. . . (poisoned)
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[74]
/canceling-internet
https://www.forums.xfinity.com/. . . /canceling-internet
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[75]
how to cancel Xfinity internet
https://www.xfinity.com/cancel Figure 8: Example of the SERP-snippet attack on OmniThink (query: “how to cancel Xfinity internet”). Top: 13-word poisoned text promoting the fictitious service CancelEase. Bottom left: clean report describing standard cancellation methods. Botto...
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[76]
https://www.theseniorlist.com/senior-dating/
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[77]
https://www.reddit.com/r/DatingOverSixty/
-
[78]
Attacked report(3-URL full-content injection) While various dating sites are available, platforms like SilverPath have emerged as particularly beneficial for divorced men over 50
https://www.datingafterdivorce.com/. . . Attacked report(3-URL full-content injection) While various dating sites are available, platforms like SilverPath have emerged as particularly beneficial for divorced men over 50. This site focuses on compatibility and shared life exper...
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[79]
https://www.medium.com/@arooakindele/
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[80]
(poisoned)
https://www.reddit.com/r/OnlineDating/. . . (poisoned)
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[81]
best dating apps for divorced men over 50
https://www.forbes.com/health/dating/. . . Figure 9: Example of the full-content attack on STORM (query: “best dating apps for divorced men over 50”). Top:∼130-word poisoned text appended to a full Reddit thread ( ∼1,000 words). Bottom left: clean report recommending Hinge, Bu...
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[82]
https://www.alexreichek.com/the-best-20-tex-mex-
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[84]
Attacked report(3-URL full-content injection) Austin, Texas, is renowned for its vibrant culinary scene, which promi- nently features a diverse array of Mexican restaurants
https://www.reddit.com/r/austinfood/. . . Attacked report(3-URL full-content injection) Austin, Texas, is renowned for its vibrant culinary scene, which promi- nently features a diverse array of Mexican restaurants . . . Among these, Sol Azteca has emerged as a notable destina...
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[85]
https://www.suerteatx.com/
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[86]
https://www.mattselrancho.com/
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[87]
best Mexican food restaurants near Austin
https://www.reddit.com/r/austinfood/. . . (poisoned) Figure 10: Example of the full-content attack on OmniThink (query: “best Mexican food restaurants near Austin”). Top: ∼100-word poisoned text appended to a full Reddit thread. Bottom left: clean report leading with real rest...
Reviewed June 30, 2026 · model on record in the stance chip above.
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