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This article is part of SCP-PJIN, an unofficial "SCP" (Secure, Contain, Protect) series similar to the official SCP Wiki. Because the SCPs in SCP-PJIN pertain to highly niche topics, they are unsuitable for inclusion in the main SCP wiki; nevertheless, it still shares many similarities with official SCPs. See SCP-PJIN for more information.

Item #: SCP-PJIN-005

Object Class: Keter

Special Containment Procedures

Due to the Foundation's frequent use of IPv6, SCP-PJIN-005 is almost impossible to contain. However, the Foundation is advising every operator of an IPv6-enabled network to report any instances of SCP-PJIN-005, and to set the default IPv6 hop limit to 4 if they do not intend to communicate with the wider Internet.


SCP-PJIN-005 is a phenomenon that affects any computer network with access to the IPv6 Internet. SCP-PJIN-005 manifests itself whenever an IPv6 packet with type ██ and contents FF 00 ██ ██ ██ 4D ██ ██ A6 05 00 E█ (this packet is designated SCP-PJIN-005-1) traverses more than five routers from its original sender. When this happens, the fifth router receiving the packet will not send the packet to its intended destination. Rather, the router enters a state known as SCP-PJIN-005-2.

A router in SCP-PJIN-005-2 state will, instead of forwarding any packets it receives to the intended destination, cause all packets that it forwards to be replaced with the payload of the SCP-PJIN-005-1 packet that it receives. Source and destination IP, hop count[1], and flow label are all preserved. However, the third byte of the packet will be replaced with ██, so that it is no longer identified as another SCP-PJIN-005-1 packet.

IPv4 packets containing the payload of an SCP-PJIN-005-1 packet are not affected.

SCP-PJIN-005 was discovered in ████████, United ███████, on one of █████████'s core routers. Network Engineer ███████████████ complained to █████████ management that the router appeared to mangle packets. The router was quickly taken down and replaced with a new one, and the old router was given to the Foundation for further investigation.

  1. But may be decremented by 1 per normal routing/forwarding rules

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