CPDLC over ATN-B1 Vulnerabilities

Summary

Multiple vulnerabilities have been discovered in the CPDLC over ATN-B1 system, which relies on unauthenticated radio frequency links. These flaws allow for unauthorized message injection, denial-of-service conditions, and session resets. While not creating an unsafe aircraft condition, they can degrade operational safety by increasing workload and delaying critical instructions. No mitigations are currently available.

Full text

ICS Advisory CPDLC over ATN-B1 Vulnerabilities Release DateAugust 07, 2026 Alert CodeICSA-26-219-01 Related topics: Industrial Control System Vulnerabilities , Industrial Control Systems View CSAF Summary ATN-B1 CPDLC relies on legacy clear text unauthenticated radio frequency links. Research demonstrates that these characteristics allow unauthorized message injection, denial-of-service conditions, and forced session resets. These vulnerabilities do not constitute an unsafe aircraft condition but can degrade operational safety margins by increasing workload, delaying safety-critical instructions, and reducing situational awareness. The following versions of CPDLC over ATN-B1 Vulnerabilities are affected: ATN-B1 CPDLC vers:all/* (CVE-2025-71409, CVE-2025-71410, CVE-2025-71411, CVE-2025-71412, CVE-2025-71413) CVSS Standard Equipment Vulnerabilities v3 7.1 Advisory Circular 90-117 Data Link Communications CPDLC over ATN-B1 Vulnerabilities Missing Authentication for Critical Function, Allocation of Resources Without Limits or Throttling, Improper Check for Unusual or Exceptional Conditions Background Critical Infrastructure Sectors: Transportation Systems Countries/Areas Deployed: Worldwide Company Headquarters Location: Global Vulnerabilities Expand All + CVE-2025-71409 Lack of authentication for Very High Frequency Data Link messages allows rogue ground stations to inject CPDLC messages leading to unexpected or misleading clearances and potential pilot confusion. This type of attack can be carried out remotely over radio frequency. View CVE Details Affected Products CPDLC over ATN-B1 Vulnerabilities Standard:Advisory Circular 90-117 Data Link Communications Product Version:Advisory Circular 90-117 Data Link Communications ATN-B1 CPDLC: vers:all/* Product Status:known_affected Remediations None availableCurrently, there is no mitigation available for CVE-2025-71409, CVE-2025-71410, CVE-2025-71411, CVE-2025-71412, CVE-2025-71413. MitigationThese vulnerabilities in the CPDLC protocol stack are exploitable in a lab environment. However, they require very specific conditions to be met and are unlikely to be exploited outside of a lab setting. MitigationOrganizations observing suspected malicious activity should follow established internal procedures and report findings to CISA for tracking and correlation against other incidents. MitigationNo known public exploitation specifically targeting these vulnerabilities has been reported to CISA at this time. These vulnerabilities have a high attack complexity. Relevant CWE: CWE-306 Missing Authentication for Critical Function Metrics CVSS Version Base Score Base Severity Vector String 3.1 7.1 HIGH CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:N/I:H/A:L 4.0 7.1 HIGH CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:N/VI:H/VA:L/SC:N/SI:H/SA:L CVE-2025-71410 Unnumbered Disconnect (U DISC) and malformed Aviation Very High Frequency Link Control frames can terminate sessions and lead to a loss of CPDLC functions requiring a reversion to voice communication and increased controller workload. This type of attack can be carried out remotely over radio frequency. View CVE Details Affected Products CPDLC over ATN-B1 Vulnerabilities Standard:Advisory Circular 90-117 Data Link Communications Product Version:Advisory Circular 90-117 Data Link Communications ATN-B1 CPDLC: vers:all/* Product Status:known_affected Remediations None availableCurrently, there is no mitigation available for CVE-2025-71409, CVE-2025-71410, CVE-2025-71411, CVE-2025-71412, CVE-2025-71413. MitigationThese vulnerabilities in the CPDLC protocol stack are exploitable in a lab environment. However, they require very specific conditions to be met and are unlikely to be exploited outside of a lab setting. MitigationOrganizations observing suspected malicious activity should follow established internal procedures and report findings to CISA for tracking and correlation against other incidents. MitigationNo known public exploitation specifically targeting these vulnerabilities has been reported to CISA at this time. These vulnerabilities have a high attack complexity. Relevant CWE: CWE-770 Allocation of Resources Without Limits or Throttling Metrics CVSS Version Base Score Base Severity Vector String 3.1 5.3 MEDIUM CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H 4.0 6 MEDIUM CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N CVE-2025-71411 Broadcast control frames can disconnect multiple aircraft simultaneously leading to delayed clearances and air traffic controller overload. This type of attack can be carried out remotely over radio frequency. View CVE Details Affected Products CPDLC over ATN-B1 Vulnerabilities Standard:Advisory Circular 90-117 Data Link Communications Product Version:Advisory Circular 90-117 Data Link Communications ATN-B1 CPDLC: vers:all/* Product Status:known_affected Remediations None availableCurrently, there is no mitigation available for CVE-2025-71409, CVE-2025-71410, CVE-2025-71411, CVE-2025-71412, CVE-2025-71413. MitigationThese vulnerabilities in the CPDLC protocol stack are exploitable in a lab environment. However, they require very specific conditions to be met and are unlikely to be exploited outside of a lab setting. MitigationOrganizations observing suspected malicious activity should follow established internal procedures and report findings to CISA for tracking and correlation against other incidents. MitigationNo known public exploitation specifically targeting these vulnerabilities has been reported to CISA at this time. These vulnerabilities have a high attack complexity. Relevant CWE: CWE-770 Allocation of Resources Without Limits or Throttling Metrics CVSS Version Base Score Base Severity Vector String 3.1 5.3 MEDIUM CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H 4.0 6 MEDIUM CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N CVE-2025-71412 Injection of false emergency or status messages over CPDLC may lead to misallocation of resources, operational confusion, and improper response actions by flight crews, traffic controllers, and ground operations. This type of attack can be carried out remotely over radio frequency. View CVE Details Affected Products CPDLC over ATN-B1 Vulnerabilities Standard:Advisory Circular 90-117 Data Link Communications Product Version:Advisory Circular 90-117 Data Link Communications ATN-B1 CPDLC: vers:all/* Product Status:known_affected Remediations None availableCurrently, there is no mitigation available for CVE-2025-71409, CVE-2025-71410, CVE-2025-71411, CVE-2025-71412, CVE-2025-71413. MitigationThese vulnerabilities in the CPDLC protocol stack are exploitable in a lab environment. However, they require very specific conditions to be met and are unlikely to be exploited outside of a lab setting. MitigationOrganizations observing suspected malicious activity should follow established internal procedures and report findings to CISA for tracking and correlation against other incidents. MitigationNo known public exploitation specifically targeting these vulnerabilities has been reported to CISA at this time. These vulnerabilities have a high attack complexity. Relevant CWE: CWE-754 Improper Check for Unusual or Exceptional Conditions Metrics CVSS Version Base Score Base Severity Vector String 3.1 7.1 HIGH CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:N/I:H/A:L 4.0 7.1 HIGH CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:N/VI:H/VA:L/SC:N/SI:H/SA:L CVE-2025-71413 Malformed or out-of-sequence frames at the Aviation Very High Frequency Link Control X.25 layers cause repeated resets which may result in increased workload and reduced situational awareness. This type of attack can be carried out remotely over radio frequency. View CVE Details Affected Products CPDLC over ATN-B1 Vulnerabilities Standard:Advisory Circular 90-117 Data Link Communications Product Version:Advisory Circular 90-117 Data Link Communications ATN-B1 CPDLC: vers:all/* Product Status:known_affected Remediations None availableCurrently, there is no miti

Indicators of Compromise

• cve — CVE-2025-71409
• cve — CVE-2025-71410
• cve — CVE-2025-71411
• cve — CVE-2025-71412
• cve — CVE-2025-71413

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