External risk intelligence

Apache Kvrocks cjson HEAP Overflow Vulnerability

CVE advisorySeverity: CRITICAL (CVSS 10.0)

CVE-2026-46752

Apache Kvrocks is a distributed key-value database designed to be used as a backend service. While it uses network protocols, such databases are typically deployed in internal, protected infrastructure or behind application layers rather than being exposed directly to the public internet.

Halo Surface Signal: 2 out of 5 — less likely to be public-facing.

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

A critical vulnerability has been identified in the cjson library used by Apache Kvrocks, specifically a Lua HEAP overflow. This could allow for significant impact on systems utilizing affected versions of Apache Kvrocks. The main concern is confirming relevance and exposure within our environment.

Redis library flaw allows code overflow.
Understand its potential impact on Kvrocks.
Confirm if our environment is affected.

Attack Path

How an attacker could exploit the issue

An attacker could exploit this vulnerability by sending specially crafted data to an exposed Apache Kvrocks instance. This could trigger a heap overflow within the cjson library used for processing Lua scripts, potentially allowing an attacker to compromise the integrity and availability of the system.

Exposed Kvrocks instance required.
Specially crafted data triggers overflow.
Leads to integrity and availability compromise.

Live Threat

Current exploitation, exposure, and threat context

A heap overflow in the cjson library used by Apache Kvrocks could allow an unauthenticated attacker to cause a denial-of-service condition or potentially execute arbitrary code. This could occur when a specially crafted request is processed by the affected service.

Server memory and availability at risk.
Triggered by network requests.
Denial of service or arbitrary code execution.

Operational Fix

Recommended remediation, mitigation, and detection steps

The vulnerability in Apache Kvrocks, stemming from a HEAP overflow in the cjson library, is a critical issue that requires immediate attention. The primary responsibility for addressing this falls to the platform or infrastructure teams managing the Kvrocks deployment. The first practical step is to identify all instances of the affected technology, assess their exposure and business criticality, and then coordinate remediation efforts based on the identified risk.

Platform or infrastructure teams should own the issue.
Verify Kvrocks instances and their network exposure.
Plan remediation based on criticality and exposure.

Supplementary metadata

CVSS vector

Validate whether this threat affects your internet-facing exposure.

Halo Threat Intelligence helps prioritize remediation with Halo Surface Signal and H/A/L/O context. Start exposure validation with a free external attack surface trial.

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Frequently asked questions

What is Apache Kvrocks?

Apache Kvrocks is a distributed key-value database built to serve as a high-performance storage backend. It is compatible with the Redis protocol, allowing developers to use familiar commands to manage data while Kvrocks handles storage on disk to provide large-scale, persistent capacity.

What is the heap overflow vulnerability in CVE-2026-46752?

This CVE-2026-46752 issue involves a memory corruption weakness known as a heap-based buffer overflow, classified as CWE-122. It exists within the cjson library used by Kvrocks to process Lua scripts. When the library receives input that exceeds its allocated memory buffer, it may overwrite adjacent memory, which can lead to system instability or allow unauthorized code execution.

How is the CVE-2026-46752 heap overflow triggered?

An attacker triggers this vulnerability by sending specially crafted data payloads to an affected Kvrocks instance. Because the flaw exists within the Lua script processing logic, the vulnerability is not triggered by standard, well-formed database queries or normal administrative commands; it specifically requires data designed to exploit the memory handling of the cjson library.

Do I need to worry if my Kvrocks instance is internal?

Halo Surface Signal indicates that Kvrocks is typically deployed in protected, internal environments rather than being exposed to the public internet. While the threat is critical, instances hidden behind firewalls or application layers face lower immediate risk compared to those directly reachable from the outside. You should still assess your network architecture to confirm if any instances have unintended external reach.

How should I respond to this Apache Kvrocks vulnerability?

First, identify all deployed instances of Kvrocks within your environment to determine which ones are running affected versions (2.0.4 through 2.15.0). Once mapped, prioritize updating those instances to version 2.16.0, which includes the necessary fixes for the cjson library flaw. Infrastructure teams should manage this transition to ensure service continuity while eliminating the memory safety risk.

References

Written by Nicholas Merritt

Nicholas Merritt is VP of Security Solutions at Halo Security. With more than 25 years across application security, vulnerability prioritization, and offensive security, he helps teams translate threat data into practical exposure validation and remediation focus. He authors Halo Threat Intelligence CVE advisories using Halo Surface Signal and H/A/L/O context to prioritize internet-facing risk.