Sigma rule: Cisco LDP Authentication Failures

A detection rule from the SigmaHQ repository, shown as its author published it. Dataset version ref-0d8272a12cc6, updated 2023-01-09T00:00:00.000Z.

Rule

Title
Cisco LDP Authentication Failures
Status
test
Level
low
Author
Tim Brown
Date
2023-01-09
File
rules/network/cisco/ldp/cisco_ldp_md5_auth_failed.yml
Commit
ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects LDP failures which may be indicative of brute force attacks to manipulate MPLS labels

Log source

product
cisco
service
ldp
definition
Requirements: cisco ldp logs need to be enabled and ingested

Detection

selection_protocol:
    - 'LDP'
selection_keywords:
    - 'SOCKET_TCP_PACKET_MD5_AUTHEN_FAIL'
    - 'TCPMD5AuthenFail'
condition: selection_protocol and selection_keywords

False positives (as the rule lists them)

  • Unlikely. Except due to misconfigurations

Tags

  • attack.initial-access
  • attack.persistence
  • attack.privilege-escalation
  • attack.credential-access
  • attack.collection
  • attack.stealth
  • attack.t1078
  • attack.t1110
  • attack.t1557

MITRE ATT&CK ids this rule names

References

Read on 2026-11-03T00:58:21.399Z under licence sigma-drl-1.1@d5f4c36a from https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/network/cisco/ldp/cisco_ldp_md5_auth_failed.yml

Sources and licences

  • SigmaHQ

    "Cisco LDP Authentication Failures" by Tim Brown (SigmaHQ). Rule: https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/network/cisco/ldp/cisco_ldp_md5_auth_failed.yml.
    Licensed under the Detection Rule License (DRL) 1.1: https://github.com/SigmaHQ/Detection-Rule-License

    Detection Rule License (DRL) 1.1

Cite this page

Dragons Eye Ransomware Tracker, "Sigma rule: Cisco LDP Authentication Failures",
entity page, dataset version ref-0d8272a12cc6, updated 2023-01-09T00:00:00.000Z,
https://ransomware-tracker.com/detections/sigma/50e606bf-04ce-4ca7-9d54-3449494bbd4b (accessed 2026-11-03).
Underlying source: SigmaHQ rule 50e606bf-04ce-4ca7-9d54-3449494bbd4b, commit ccbb0369507f796db0b0ae6854c8a2be471b9d84.

Pages change. The dataset version identifies the data, but no archive of old versions is kept, so this citation cannot be replayed later.