External risk intelligence

Extended Passport Protocol Memory Safety Vulnerability Allows Unauthenticated Network Attacks.

CVE advisorySeverity: CRITICAL (CVSS 10.0)

CVE-2026-44756

The vulnerability involves a network-accessible protocol processing library. While it is reachable over the network, the Extended Passport Protocol is typically used in specific enterprise or backend service contexts rather than being a standard, publicly exposed internet-facing service by default.

Buffer Overflow

Halo Surface Signal: 3 out of 5 — possibly public-facing.

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

This advisory details a critical memory safety vulnerability within the Extended Passport Protocol (EPP) processing library. An unauthenticated attacker could exploit a malformed network request to cause program termination and potentially impact the confidentiality, integrity, and availability of the affected application. The main concern at this stage is to confirm if this protocol is in use within our environment and to what extent it may be exposed.

Flaw in passport protocol processing could crash applications.
Unauthenticated network access could compromise application data.
Confirm usage and exposure of this specific protocol.

Attack Path

How an attacker could exploit the issue

An attacker could target an application that processes the Extended Passport Protocol by sending a specially crafted network request. This request, containing a malformed EPP header, could trigger a memory safety issue within the protocol's processing library. If successful, this could lead to unexpected program behavior, potentially impacting the application's confidentiality, integrity, and availability.

No authentication required for attack.
Malformed EPP header in network request.
High impact on confidentiality, integrity, availability.

Live Threat

Current exploitation, exposure, and threat context

A memory safety flaw in the Extended Passport Protocol (EPP) processing library could allow an unauthenticated attacker to disrupt application services. When the library processes a specially crafted network request with a malformed EPP header, it may lead to unexpected program behavior or crashes. This could affect the confidentiality, integrity, and availability of the application.

Application service availability
Malformed network request
Application disruption

Operational Fix

Recommended remediation, mitigation, and detection steps

Real-World Ownership --------------------

Given the vulnerability in the Extended Passport Protocol (EPP) processing library, the first step involves identifying which application or service utilizes this library. Ownership will likely fall to the platform or application team responsible for that service. The immediate priority is to confirm the presence of the affected EPP processing, assess its exposure and criticality, and then coordinate a remediation plan based on the risk assessment.

Application and platform teams own.
Verify EPP processing presence and exposure.
Plan remediation based on assessed risk.

Supplementary metadata

CVSS vector

Validate whether this threat affects your internet-facing exposure.

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Frequently asked questions

What is the Extended Passport Protocol (EPP) processing library?

The Extended Passport Protocol (EPP) processing library is a software component responsible for parsing and handling specific network communication headers used for identity or session validation. It acts as an intermediary, allowing applications to securely interpret traffic and manage credentials within enterprise architectures. Because it manages protocol-level data, it is a foundational piece of code that must accurately handle incoming network requests to maintain system stability and security.

Why is this memory safety issue classified as a weakness?

This vulnerability is classified as CWE-120, which refers to Buffer Copy without Checking Size of Input. In simple terms, the software fails to properly verify the length of data provided in an EPP header before writing it to a memory buffer. Because the library does not enforce strict limits, an attacker can provide malformed input that overflows these boundaries, leading to undefined application behavior, potential data corruption, or forced program termination.

How does an attacker trigger CVE-2026-44756?

An attacker triggers this vulnerability by sending a specially crafted network request containing a malformed header to an application that uses the vulnerable library. The attack requires no prior authentication, meaning anyone with network access to the service can attempt it. Importantly, standard, well-formed EPP traffic does not trigger this flaw; the library only fails when it encounters specific, intentionally broken header structures designed to exploit its memory handling logic.

Is my system at risk if it uses this protocol?

According to Halo Surface Signal, this vulnerability affects network-accessible protocol libraries, but its risk depends on your deployment. EPP is typically used for internal backend service communication rather than public-facing traffic. However, if your service is configured to accept EPP requests from untrusted segments or the internet, it is at higher risk. You should evaluate if the service is reachable from outside your local network or from low-trust zones.

How should I respond to this vulnerability?

Your first step is to audit your environment to identify which applications or platform services utilize the Extended Passport Protocol. Do not assume the library is present everywhere; confirm its active usage through software inventory or dependency analysis. Once identified, work with the relevant application teams to assess the service's network exposure and prioritize the implementation of official patches or security updates provided by the vendor.

References

me.sap.com/notes/3747649

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.