Description

A flaw has been found in sigoden aichat up to 0.30.4. This affects an unknown function of the file src/serve.rs of the component API Endpoint. This manipulation causes uncontrolled memory allocation. The attack can be initiated remotely. The exploit has been published and may be used. The vendor was contacted early about this disclosure but did not respond in any way.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "5.3",
  "pubDate": "2026-09-02T20:17:42.753Z",
  "pubdate": "2026-09-02T20:17:42.753Z",
  "executiveSummary": "A critical vulnerability exists in sigoden aichat versions up to 0.30.4, specifically within the API endpoint functionality implemented in src/serve.rs. The flaw allows for uncontrolled memory allocation triggered by remote actors.\nThis vulnerability is categorized as an uncontrolled resource consumption issue. By sending specially crafted requests to the affected API endpoint, an unauthenticated remote attacker can force the application to allocate excessive amounts of memory.\nThe primary risk implication is a Denial of Service (DoS) condition, as the rapid and unrestrained memory growth leads to exhaustion of available system resources, potentially causing the application or the host process to crash.\nGiven that the exploit has been publicly disclosed and the vendor has not responded to vulnerability reports, systems running vulnerable versions of aichat are at an elevated risk of targeted exploitation. There are no authentication requirements for an attacker to initiate this request, meaning the attack surface is exposed to any network entity capable of reaching the service.",
  "technicalDetails": "The vulnerability resides in the src/serve.rs file of the sigoden aichat component, which serves as the entry point for API requests. The root cause of this flaw is the lack of proper bounds checking or resource constraints when handling incoming data payloads or processing specific requests within the API endpoint logic.\nDuring the processing of a request, the application fails to adequately validate the size of data before performing memory allocation. In a scenario where the application expects input, an attacker can transmit an oversized or malformed request that forces the underlying memory management routines to allocate an excessive or unbounded amount of heap space. Because this process lacks intermediate verification or size limiting, the application continues to commit memory until the process hits the operating system's memory limits, triggering an Out-of-Memory (OOM) event.\nThe attack flow proceeds as follows: First, the attacker identifies a reachable instance of the aichat API endpoint. Second, the attacker crafts a malicious request—potentially containing headers or body content designed to trigger the vulnerable allocation code path in src/serve.rs. Third, as the application parses this input, the vulnerable routine executes an allocation request based on the attacker-supplied parameters without sanitizing the input against pre-defined capacity constraints. Finally, the rapid, uncontrolled memory allocation leads to immediate resource exhaustion.\nThis vulnerability is particularly dangerous because it can be exploited remotely over the network without the need for prior authentication or elevated privileges. Since the exploitation does not require executing arbitrary code but rather exploits the application's internal memory management logic, it bypasses many traditional signature-based security controls. The impact is a total loss of availability for the aichat service, as the process will be terminated either by the system's OOM killer or by internal memory allocation failures. Post-exploitation, the service remains unavailable until manually restarted, though the lack of input validation suggests that the service remains susceptible to immediate re-exploitation if the traffic pattern is repeated."
}