CVE-2026-123664 in gcn.nasa.gov
Summary
by MITRE • 11/06/2026
A security flaw has been discovered in nasa-gcn gcn.nasa.gov up to b299b562af665878964b981a459f0a9c04b11adf. This issue affects some unknown processing of the file /user/email of the component Email Notification Handler. Performing a manipulation of the argument Recipient results in improper authorization. The attack is possible to be carried out remotely. The exploit has been released to the public and may be used for attacks. This product adopts a rolling release strategy to maintain continuous delivery. Therefore, version details for affected or updated releases cannot be specified. The pull request to fix this issue awaits acceptance.
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Analysis
by VulDB Data Team • 11/06/2026
The vulnerability identified in nasa-gcn involves a critical authorization flaw within the Email Notification Handler component of the gcn.nasa.gov system. This security defect specifically impacts the processing logic associated with the /user/email file path, where improper access control mechanisms allow for unauthorized operations. The core technical issue stems from how the Recipient argument is handled during email notification generation and dispatching processes. When an attacker manipulates this input parameter, they can bypass intended authorization checks, effectively gaining the ability to send emails through the system without proper authentication or permission validation. This represents a classic case of broken access control where user-supplied data influences security-critical decisions without adequate verification against established policy rules.
From a technical perspective, this flaw aligns with CWE-269 Improper Privilege Management and potentially CWE-732 Incorrect Permission Assignment for Critical Resource depending on the specific implementation details of how permissions are evaluated before processing the recipient list. The vulnerability allows remote exploitation, meaning an attacker does not need local access or prior authentication to leverage this weakness. By crafting malicious requests that manipulate the Recipient field, external actors can exploit the system's trust in input parameters to perform actions beyond their authorized scope. This could lead to unauthorized email dispatching, which may be used for phishing campaigns, spam distribution, or further reconnaissance activities against NASA’s internal and external communication channels.
The operational impact of this vulnerability is significant due to the nature of the affected component as an Email Notification Handler. Compromise of this functionality can result in reputational damage if malicious emails are sent appearing to originate from official NASA systems. Additionally, it poses a risk of information leakage or social engineering attacks targeting other stakeholders who receive these unsolicited messages. Since the product utilizes a rolling release strategy for continuous delivery, version-specific mitigation details cannot be provided through traditional patch notes. Instead, security updates are integrated continuously into the main development branch, making timely deployment of fixes dependent on rapid review and acceptance cycles rather than discrete version releases.
The exploit code has already been released to the public, increasing the likelihood of widespread automated attacks against instances running affected versions up to commit b299b562af665878964b981a459f0a9c04b11adf. This situation places immediate pressure on development teams to prioritize the pending pull request that addresses this authorization bypass. Until a fix is merged and deployed, systems remain vulnerable to remote exploitation via manipulated recipient arguments in email notification requests. Security monitoring should focus on detecting anomalous patterns in email dispatch logs or unusual API calls targeting the /user/email endpoint with suspiciously formatted or unauthorized recipient lists.
Mitigation strategies must include both immediate defensive measures and long-term architectural improvements. In the short term, implementing strict input validation for all fields involved in recipient specification is essential to ensure that only authorized addresses are processed by the notification handler. Deploying web application firewalls configured to detect and block requests with malformed or excessively large recipient lists can provide an additional layer of defense while waiting for code fixes. Long-term solutions should involve adopting a zero-trust architecture where every request, regardless of origin, undergoes rigorous authentication and authorization checks before any sensitive operation is executed. Integrating automated security testing into the continuous delivery pipeline will help prevent similar flaws from reaching production environments in future releases.
This incident highlights the importance of robust access control models in components handling external communications within critical infrastructure systems like NASA’s Ground Network. The ATT&CK framework categorizes such behaviors under T1534 Internal Spearphishing if used for lateral movement or data exfiltration, emphasizing the need for comprehensive logging and anomaly detection capabilities to identify potential abuse early. Organizations relying on similar notification services should audit their own implementations of email handling logic to ensure that recipient validation is not solely dependent on client-side checks but enforced rigorously at the server level with explicit permission verification against user roles and system policies.