Cybersecurity Standard Abused as Internal Classification Tool Leaves Organizations Vulnerable
A concerning trend has emerged in various organizations attempting to use the Traffic Light Protocol (TLP) standard as a replacement for their internal information classification schemes. While TLP is a well-intentioned standard designed to facilitate secure information sharing, its misuse can lead to confusion and compromised security.
At first glance, it may seem logical to adopt TLP’s simple set of labels to restrict the sharing of sensitive information within an organization. However, this approach overlooks the fundamental purpose of TLP: to specify with whom information may be shared, not how it should be protected. Internal classification schemes, on the other hand, define requirements for encryption, storage, access control, and retention of information with different sensitivity levels.
Using TLP as a replacement for internal classification schemes can lead to misunderstandings about information handling rules. For instance, an organization may allow documents classified as “Sensitive” to be sent to customers, but only in encrypted emails or on encrypted USB drives. A TLP label alone does not convey these requirements, forcing organizations to create custom classification schemes that blend TLP labels with their own internal guidelines.
Furthermore, the sharing restrictions defined by TLP do not necessarily align with what one might expect from similarly named internal classification levels. For example, an organization using TLP:GREEN to mark documents intended for internal use may inadvertently permit further distribution among external security partners, despite its original intention. Similarly, TLP:AMBER’s permission for sharing within the recipient’s organization and clients on a need-to-know basis does not necessarily correspond to what an organization considers “Confidential” information.
A related issue arises when TLP labels are assigned based on sensitivity levels rather than who should be able to receive the information. A network diagram might be marked TLP:RED simply because someone considers it “Highly Confidential,” even though several teams or external contractors may need access to it. In such cases, the label either makes legitimate sharing unnecessarily difficult or is routinely ignored.
While organizations can define additional restrictions or their own interpretations of these labels, doing so effectively means creating a custom classification scheme that only looks like TLP. This can lead to misunderstandings whenever information is exchanged with others who follow the actual standard.
In conclusion, while TLP has its place in facilitating secure information sharing within an organization, especially when it comes to threat intelligence and security-related information, using it as a replacement for internal classification schemes is not recommended. Organizations should maintain separate classification systems that define requirements for encryption, storage, access control, and retention of sensitive information. By doing so, they can ensure clear communication about information handling rules and avoid the pitfalls associated with misusing the TLP standard.
Source: SANS ISC — 2026-10-10