In some implementations, an egress network device of a multiprotocol label switching (MPLS) network may exchange Internet key exchange (IKE) messages with an ingress network device of the MPLS network to establish a security association between the egress network device and the ingress network device. The egress network device may receive an MPLS packet that includes an MPLS header, a secure MPLS data header, and an MPLS payload. The egress network device may process the MPLS header to determine a label associated with a label-switched path (LSP) and a secure function indicator. The egress network device may decrypt, using a secure function identified based on the secure MPLS data header, the MPLS payload to generate a decrypted packet. The egress network device may transmit the decrypted packet towards a destination device.