Julia Kristeva, at 76, is one of Europe’s most decorated public intellectuals. Her more than 30 books have covered topics including linguistics, psychoanalysis, literary theory and feminism. Her many prestigious honors include the Vaclav Havel Prize, the Hannah Arendt Prize and France’s Commander of the Legion of Honor.

But now, a furor has arisen over whether it is time to add a more surprising line to her résumé: Bulgarian secret agent.

The notion surfaced on Tuesday, when the Bulgarian government commission charged with reviewing the files of the country’s notorious Communist-era secret service released a terse document alleging that the Bulgarian-born Ms. Kristeva, who has lived in France since 1966, had served in the early 1970s as an agent known by the code name “Sabina.”

The allegation was greeted with shocked disbelief by those immersed in the work of Ms. Kristeva, who is known for her staunch defense of European democratic ideals and opposition to all “totalitarianisms,” as she puts it, whether state Communism, American-style identity politics or religious fundamentalism.