CVE-2026-115801: Kakao khaiii JSON Config File Linear.cpp open out-of-bounds
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 hiddendim/classnum 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.
Affected Software
Event History
Frequently Asked Questions
Who is realistically exposed to this issue?
Exposure is limited to Kakao khaiii installations up to 0.4 where a local attacker can write to the resource directory supplied through --rsc-dir. The maintainer states that this directory is intended to be trusted input, comparable to a binary or shared library.
What does an attacker need to exploit it?
The attacker needs local access and write permission to the khaiii resource directory, allowing modification of JSON configuration values such as hidden_dim or class_num. Public exploit code is available.
Is this a meaningful additional risk if an attacker can already modify the resource directory?
The vendor notes that an attacker with write access to that directory can already alter analysis results without exploiting this defect. The vulnerability adds an out-of-bounds read condition, but it does not remove the prerequisite of resource-directory write access.
What can be done if patching is not possible?
Restrict write access to the --rsc-dir resource directory and treat its contents as trusted deployment artifacts. This is particularly relevant because affected releases are no longer supported by the maintainer.