What is the CVSS score of CVE-2026-67974?

CVE-2026-67974 has a CVSS 3.1 base score of 7.5 (High). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. EPSS exploitation probability: 0.2%.

Which versions of NASA cFS are affected by CVE-2026-67974?

NASA Core Flight System (cFS) v7.0.1 is vulnerable to remote denial-of-service attacks that could disrupt critical spacecraft and mission operations.

How to fix or mitigate CVE-2026-67974?

Within 24 hours, identify all instances of cFS v7.0.1 deployed in your environment and determine which have network exposure to the Software Bus Network (SBN) interface. Within 7 days, implement network segmentation and firewall rules to restrict access to SBN interfaces from untrusted networks, and deploy packet inspection or rate limiting to detect and block malformed subscription requests. Within 30 days, monitor official cFS project advisories for patch availability and develop a migration plan to patched versions when released.

NASA cFS CVE-2026-67974

EUVD-2026-52508 HIGH

Improper Input Validation (CWE-20)

2026-08-03 mitre

GHSA-p5hx-9q84-87hp

Denial Of Service N A

7.5

CVSS 3.1 · Vendor: mitre

Severity by source

Vendor (mitre) PRIMARY

7.5 HIGH

AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

vuln.today AI

7.5 HIGH

SBN accepts unauthenticated peer packets by design so PR:N and AV:N are correct; impact is availability-only with no scope change, matching the crash-only DoS behavior described.

3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Primary rating from Vendor (mitre).

CVSS VectorVendor: mitre

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Lifecycle Timeline

Analysis Generated

Aug 06, 2026 - 22:23 vuln.today

CVSS changed

Aug 06, 2026 - 22:22 NVD

7.5 (HIGH)

CVE Published

Aug 03, 2026 - 00:00 cve.org

UNKNOWN (no severity yet)

CVE Published

Aug 03, 2026 - 00:00 cve.org

HIGH 7.5

DescriptionCVE.org

A parser boundary flaw in the Software Bus Network (SBN) application's peer subscription message handling in NASA cFS v7.0.1 allows attackers to cause a Denial of Service (DoS) via sending a crafted packet.

AnalysisAI

Remote denial of service in NASA Core Flight System (cFS) v7.0.1 allows unauthenticated network attackers to crash the Software Bus Network (SBN) application by sending a crafted peer subscription packet that triggers a parser boundary flaw. The CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U vector confirms no authentication or user interaction is required, making this trivially reachable against any exposed SBN interface. Despite the high CVSS score of 7.5, the EPSS score of 0.16% at the 5th percentile and absence of a CISA KEV listing or public exploit code suggest no public exploitation activity at time of analysis.

Technical ContextAI

NASA's Core Flight System (cFS) is an open-source, reusable flight software framework designed primarily for spacecraft and aerospace mission applications. The Software Bus Network (SBN) is a cFS plug-in application that enables inter-node Software Bus messaging across networked flight computers, allowing processes on different nodes to publish and subscribe to messages as if they were on the same local bus. The vulnerability is classified as CWE-20 (Improper Input Validation), with the root cause being a 'parser boundary flaw' in the peer subscription message handling logic - the parser fails to properly validate the bounds or structure of incoming peer subscription packets, which can lead to an out-of-bounds read, unexpected state, or process crash that terminates the SBN application. The CPE identifier provided (cpe:2.3:a:n/a:n/a) is uninformative and does not enumerate product scope beyond what the description states; the canonical source is the GitHub repository at https://github.com/nasa/cFS.

RemediationAI

No vendor-released patch version has been identified at time of analysis. The issue is tracked at https://github.com/nasa/cFS/issues/1074, which should be monitored for upstream fixes and tagged releases. As compensating controls, operators should restrict network reachability of the cFS SBN peer subscription interface to only trusted, known peer nodes using host-based or network-level firewall rules - this directly neutralizes the AV:N attack vector and is the most impactful mitigation with no functional side effects for closed mission networks. If inter-node messaging via SBN is not required for the specific mission configuration, disabling the SBN application entirely removes the attack surface, though this prevents distributed Software Bus communication across nodes. Where network filtering is not feasible, deploying an ingress packet filter or application-layer gateway to validate peer subscription message structure before forwarding to the SBN process provides an additional layer. Monitor https://github.com/nasa/cFS for patch availability.