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Re:LLMs could control their host machines by exploiting infe... by angry_octet on Monday August 24, 2026 @05:22PM (#49426009)
People seem very confused about this article. It isn't talking about exploits of sandboxes, it is about attacking the inference engine (e.g. vLLM or llama.cpp or SGlang) via its http interface.

vLLM has had exploits in the past, and it is rapidly developing. An advanced LLM has a good chance of being able to exploit vLLM. A clever local LLM might even task a powerful cloud hosted LLM for assistance.

For this reason we run vLLM on a separately sandboxed VM on a firewalled VLAN. Software updates and models (from Dev/Test env) get pushed onto Prod from an external cache, machine syslog, nvidia load monitoring and vLLM query telemetry out to their loggers, but that is all. No DNS, no AD/LDAP, nothing. Firewall on hosts and VM hosts. Log and telemetry processing done on a completely separate set of VMs in their own isolated subnet, producing reports and alerts that are tightly formatted.

Re:LLMs could control their host machines by exploiting infe... by jimmaswell on Tuesday August 25, 2026 @12:35AM (#49429124)
I can only see LLM's forcing a perpetual stalemate for application exploits. Projects will start adding "tell the strongest no-guardrails open weights model to pentest it for 12 hours" to their CICD pipelines. Technical exploits being a dead end, attackers focus their agents on large-scale social engineering. Spamming Discord and Facebook is the new war dialing. Multi-year /goal sessions culminating in gaining a position of trust and sabotaging the CICD pipeline's pentest step since getting anything past it would be intractable. Interesting times indeed.
Re:LLMs could control their host machines by exploiting infe... by rithdmc on Tuesday August 25, 2026 @06:20AM (#49431445)
If projects start adding "tell the strongest no-guardrails open weights model to pentest it for 12 hours" to their CICD pipelines, then researchers will prompt a pentest for 14 hours.
Re:LLMs could control their host machines by exploiting infe... by angry_octet on Tuesday August 25, 2026 @06:19PM (#49441464)
Different models test to find different attack paths. Attackers with bigger libraries of attack techniques will be able to train more dangerous models.

There will also be models that make better use of tools, like static analysis and fuzzing, and they will find different defects. Social engineering is going to be a big skill to learn too, as it is a much softer skill.

Re:LLMs could control their host machines by exploiting infe... by jimmaswell on Wednesday August 26, 2026 @01:32AM (#49444393)
There will be a plateau at some point, if not 12 then something.
Re:LLMs could control their host machines by exploiting infe... by rithdmc on Wednesday August 26, 2026 @06:41AM (#49446728)
This was a deliberately poor phrasing of the "10 foot wall, 12 foot ladder" adage.
Re:LLMs could control their host machines by exploiting infe... by jimmaswell on Thursday August 27, 2026 @12:00PM (#49466985)
Right, but the comparison isn't perfect here because wall height is linear in the analogy, but searching for exploits in an existing piece of code reaches a point where either there are none left to find, or finding the next exploit would take years. That's the stalemate point I referred to. (Any high-stakes project may end up having its own "red team" agent/s running 24/7 too.)
Re:LLMs could control their host machines by exploiting infe... by rithdmc on Friday August 28, 2026 @11:09AM (#49479721)
I know that, as time goes on, it feels like we have less hours in the day, but time is also linear.
Re:LLMs could control their host machines by exploiting infe... by beyarkay on Tuesday August 25, 2026 @04:56AM (#49430859)
> it is about attacking ... via its http interface

Say more? HTTP isn't mentioned in the article. The article talks about bugs in the parser that ingests token sequences.

Re:LLMs could control their host machines by exploiting infe... by kzrdude on Tuesday August 25, 2026 @06:36AM (#49431574)
That reads to me as if the GP confabulated a different exploit target than what the article mentioned (or the article changed), but it's also a threat that should be taken seriously.
Re:LLMs could control their host machines by exploiting infe... by angry_octet on Tuesday August 25, 2026 @07:52AM (#49432348)
How do you think the tokens get to the vLLM instance? Telepathy?
Re:LLMs could control their host machines by exploiting infe... by angry_octet on Tuesday August 25, 2026 @08:13AM (#49432617)
@hobofan How would you access that parser?
Re:LLMs could control their host machines by exploiting infe... by hobofan on Tuesday August 25, 2026 @12:31PM (#49436722)
_you_ wouldn't. The blog post is about vulnerabilities that happen inside the inference engine, and not via external interfaces accessible via HTTP. The token parser is involved both on the way in (where yes, you would as user supply it likely via HTTP), as well as the way out of the LLM (where there are very few, less hardened layers when interfacing with the parser).

e.g. for a vulnerability exploit in the parser, an LLM can be trained with a specific input sequence that would output a fixed malicious payload to output eval-able content, as outlined in the article.

Re:LLMs could control their host machines by exploiting infe... by angry_octet on Tuesday August 25, 2026 @06:14PM (#49441417)
The attacker supplies the context that triggers these bugs via the http interface. There is no other way to supply it with context.

Vulnerable code could exist in token generation and in hook recognition and tool call parsing [1]. There is also significant scope for mischief in tool ID mapping between models and harnesses, as these are done by untyped numeric IDs, with varying schema[2]. Routers also introduce vulnerability paths as they inspect these tokenized (json) sequences and act in them, e.g. to match models with stricter call signature regex. [3] Parallel tool calling is also an interesting surface for exploits.

[1] https://docs.vllm.ai/en/stable/api/vllm/tool_parsers/#vllm.t...

[2] https://docs.mistral.ai/resources/cookbooks/concept-deep-div...

[3] https://docs.litellm.ai/docs/completion/function_call

Re:LLMs could control their host machines by exploiting infe... by hobofan on Wednesday August 26, 2026 @09:22AM (#49448708)
I'm not saying that the HTTP interface is not an attack surface, but that securing that attack surface (as one may assume in a simple security model) is not enough to protect against that class of attacks, as no level of introspecting the input will help predict and secure against malicous output.
Re:LLMs could control their host machines by exploiting infe... by angry_octet on Wednesday August 26, 2026 @06:57PM (#49457063)
This is misunderstanding the attack. The potentially malicious output tokens are processed entirely by classical text processing techniques, i.e. parsing, in order to enable tool calling on the client and via MCP servers. Garden variety vulnerabilities can occur on the inference server, but are amenable to modest levels of software engineering competency.

Basically, it's a regex, don't fuck it up.

Re:LLMs could control their host machines by exploiting infe... by hobofan on Tuesday August 25, 2026 @08:12AM (#49432599)
> the parser that ingests token sequences
Re:LLMs could control their host machines by exploiting infe... by j16sdiz on Tuesday August 25, 2026 @08:24AM (#49432755)
> ... the parser that ingests token sequences.

which is exposed via http

Re:LLMs could control their host machines by exploiting infe... by shevy-java on Tuesday August 25, 2026 @06:58AM (#49431789)
Did you write this for another article on hackernews? I am not sure this applies to the article mentioned here.
Re:LLMs could control their host machines by exploiting infe... by drillsteps5 on Tuesday August 25, 2026 @12:35PM (#49436791)
Very good point, it's about exploiting inference engine itself, and not the agentic stuff.

I found it lacking details. All these things do is split the input into tokens, encode them, feed to the input, run the inference, collect the output, decode, convert to tokens, assemble the final text, and output (leaving aside multi-modal capabilities for now). What exactly can be exploited here? Aside from usual things like buffer overruns etc.

It does mention that vLLM at some point ran eval() on final output (?) which was confusing, why would it do that? It's an inference engine, not an agent.

So interesting topic, but lacks details.

Edit: many (all?) of them have http endpoints, so that obviously can be exploited, but I don't think it would qualify as exploiting inference, it's just hacking the http service.

Re:LLMs could control their host machines by exploiting infe... by angry_octet on Tuesday August 25, 2026 @06:22PM (#49441501)
You get to the engine via http. Also once you've exploited the engine instance / host you can C2 via http. We're not talking about vulnerabilities in http.

There is lots of surface inside the engine, see links in https://news.ycombinator.com/item?id=49441417

Re:LLMs could control their host machines by exploiting infe... by yencabulator on Thursday August 27, 2026 @12:36PM (#49467546)
> It does mention that vLLM at some point ran eval() on final output (?) which was confusing, why would it do that? It's an inference engine, not an agent.

There's a couple of different conventions for what the LLM generates for tool calls, I think the code in vLLM is converting it from whatever Qwen3 was trained for to whatever convention the HTTP API wants to expose.

That part about using eval in 2025 got me to add "#naive" to my notes about vLLM. Total WTF. This should never have been done.

https://github.com/vllm-project/vllm/pull/21396#discussion_r...