Malayan Heroine

Use the nickname You Loy-De to identify a Malayan heroine, then research her children to construct the flag.

By 0xG10D | Last updated: August 30, 2025 | 1 minute read
Medium #ctf#bahtera-3108#osint

Malayan Heroine

Challenge Overview

  • Event: Bahtera 3108 2025
  • Category: OSINT
  • Points: 100

The challenge supplied two clues:

Her husband’s nickname was “You Loy-De”.

3108{the heroine daughter}

Spaces were to be replaced with underscores.

Identifying the Heroine

Searching for the nickname led to Sybil Kathigasu. The source states that the local Chinese community knew her husband, Dr. Kathigasu, by the Hakka nickname You Loy-De.

You Loy-De nickname clue in the Sybil Kathigasu article

Finding Her Daughter

The family information listed the following children:

  1. William Pillay (25 October 1918), adopted
  2. Michael Kathigasu (26 August 1919), who died 19 hours after birth
  3. Olga Kathigasu (26 February 1921 – 6 September 2014)
  4. Dawn Kathigasu (21 September 1936 – unknown), who married William Bruce Spalding in London on 1 September 1956 and later had children

Using the heroine’s daughter named in the source and replacing the space with an underscore produced the recorded flag.

Flag

3108{Dawn_Kathigasu}

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