External risk intelligence

ION-DTN Integer Overflow Heap Corruption

CVE advisorySeverity: CRITICAL (CVSS 9.2)

CVE-2026-124001

ION-DTN is a Delay-Tolerant Networking implementation used for specialized space and research communications. While the vulnerability exists in the DGR convergence layer, this software is typically deployed within isolated, research, or mission-specific internal network infrastructures rather than exposed as public-facing internet services or common enterprise gateways.

Integer Overflow

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

This advisory concerns a vulnerability in NASA JPL's ION-DTN software, specifically an integer overflow within its data retransmission layer. This flaw could allow for heap memory corruption, potentially leading to denial of service or even remote code execution. The main concern is to confirm whether this specialized software is in use and exposed within our environment.

Software flaw could corrupt memory and cause service disruption.
Specialized software, relevance must be confirmed.
Understand potential exposure of critical communication systems.

Attack Path

How an attacker could exploit the issue

An attacker could exploit this vulnerability by sending specially crafted datagrams over internal or custom transports. This allows them to trigger an integer overflow in the Datagram Retransmission (DGR) convergence layer, corrupting heap memory. Successful exploitation could lead to denial of service or potentially remote code execution.

Requires network access to vulnerable component.
Triggered by sending malformed datagrams.
Risk of denial of service or code execution.

Live Threat

Current exploitation, exposure, and threat context

The ION-DTN software's Datagram Retransmission (DGR) convergence layer could be vulnerable to an integer overflow. This occurs when a crafted 64-bit value, used for calculating buffer sizes, wraps around a 32-bit calculation. If the DGR convergence layer is utilized, this could lead to heap memory corruption, potentially causing a denial of service or allowing for remote code execution.

Heap memory corruption.
Malicious datagrams over DGR traffic.
Denial of service or code execution.

Operational Fix

Recommended remediation, mitigation, and detection steps

The ION-DTN software, particularly its Datagram Retransmission (DGR) convergence layer, is susceptible to an integer overflow vulnerability. This issue could allow for heap corruption, potentially leading to denial of service or remote code execution. Given the specialized nature of ION-DTN, likely used in research or mission-specific internal networks rather than public-facing services, immediate action would involve identifying internal deployments, assessing their criticality and exposure, and coordinating with the platform or infrastructure teams responsible for this specialized technology.

Identify ION-DTN asset owners.
Verify internal deployment reachability.
Plan risk-based remediation.

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.

Free EASM Trial See How Signal Works

Frequently asked questions

What is NASA JPL ION-DTN?

ION-DTN is an implementation of Delay-Tolerant Networking developed by NASA JPL. It is designed to enable communication across networks that experience frequent disruptions or high latency, such as those used in specialized space exploration, satellite communications, and research projects.

What is the vulnerability in CVE-2026-124001?

This CVE describes an integer overflow and a subsequent out-of-bounds write (CWE-190 and CWE-787). The software incorrectly calculates memory allocation sizes for data packets; an attacker can provide a specifically crafted 64-bit value that causes the calculation to wrap around when processed by the 32-bit allocation logic, leading to heap memory corruption.

How is this vulnerability triggered?

The flaw is triggered by sending malformed datagrams specifically designed to interact with the Datagram Retransmission (DGR) convergence layer. The vulnerability requires network access to the component; however, simple, standard traffic that does not attempt to manipulate the svcDataLength value will not trigger the overflow condition.

Is this vulnerability a risk for my public-facing services?

According to Halo Surface Signal, this software is typically deployed in isolated, research, or mission-specific internal networks. Because it is rarely used for standard internet-facing services, the risk is generally lower than for common enterprise software, though you should verify your specific internal architecture.

How should I respond if I am running ION-DTN?

First, identify all systems within your environment where ION-DTN is deployed. Because this software is often used for specialized or mission-critical communication, coordinate with your infrastructure or platform teams to assess the network reachability of these components and plan a risk-based update or configuration change.

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.