---
id: "CVE-2026-115801"
kind: "vulnerability"
aliases: ["CVE-2026-115801"]
title: "Kakao khaiii: crafted model config causes out-of-bounds read locally"
severity: "medium"
cvss: 5.3
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["khaiii", "linux", "local-install", "package", "python"]
not_affected_if: ["no-local-untrusted-users", "read-only-resource-dir", "supported-version"]
published_at: "2026-10-23T22:16:57+00:00"
first_seen_at: "2026-10-23T23:44:51+00:00"
updated_at: "2026-10-25T04:18:48+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-115801", "first_seen_at": "2026-10-23T23:44:51+00:00"}]
---

# Kakao khaiii: crafted model config causes out-of-bounds read locally

Kakao khaiii, a Korean morphological analyzer library, reads past a buffer in Linear::open when a model config file sets hidden_dim or class_num to crafted values. A local user who can write to the resource directory can trigger the out-of-bounds read, and the vendor says an attacker with that write access could already change analysis results directly.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the installed khaiii version with `pip show khaiii` or the build's version string; affected versions are up to `0.4`
- Confirm whether the resource directory passed to `--rsc-dir` is writable by users other than the service account

## Fix

- The maintainer no longer supports affected versions; move to a supported khaiii release or replace the library
- Restrict write access to the khaiii resource directory to the deploying account only

## Timeline

- 2026-10-23T23:44:51+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-115801

## From the sources

A security flaw has been discovered in Kakao khaiii up to 0.4. The impacted element is the function khaiii::nn::Linear::open of the file src/main/cpp/khaiii/nn/Linear.cpp of the component JSON Config File Handler. The manipulation of the argument hidden_dim/class_num results in out-of-bounds read. The attack requires a local approach. The exploit has been released to the public and may be used for attacks. The vendor explains: "khaiii treats the resource directory (--rsc-dir) as trusted input, like a binary or a shared library. To use this defect, an attacker must already be able to write to that directory. With that access, an attacker can change the analysis results without this defect." This vulnerability only affects products that are no longer supported by the maintainer.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_