South Africa's top corruption fighter has condemned a newspaper for publishing extracts from her report, which allegedly says President Zuma should repay some of the $20m (£12m) spend on upgrades to his rural home.
Thuli Madonsela said it was "unethical and unlawful" to publish her report.
According to the Mail and Guardian, she said Mr Zuma had derived "substantial benefits" from the upgrade.
The government says the improvements were needed for national security.
It has gone to court to block publication of Ms Madonsela's report.
Last week, several newspapers defied a government warning not to publish photographs of the residence in Nkandla.
The BBC's Pumza Fihlani in Johannesburg says the row is one of the biggest issues in South Africa at the moment, ahead of elections due early next year.
Opposition parties have condemned it as a waste of public money, while the governing ANC says it believes he has done nothing wrong.
Mr Zuma's office has declined to comment on the Mail and Guardian article.
The newspaper says it has had "direct access" to the provisional report by Ms Madonsela, the public protector.
It said the upgrades included a visitors' lounge, amphitheatre, cattle enclosure, swimming pool and houses for the president's relatives.
It estimates the cost of those additions to be about 20m rand ($2m: £1.2m).
The newspaper said it published the article because "all the evidence points to a systematic attempt by the government to shield disclosures about the scandal from public view".
"There are good reasons for fearing that the security ministers who tried to interdict Madonsela earlier this month may be planning further litigation to block its release," it said.
Ms Madonsela has distanced herself from the article and the quotes that have been attributed to her.
She said recently that her final report would be released in about a month.