The U.S. Department of Education has acknowledged that a software upgrade this week to its online system for managing direct student loans accidentally mixed up the data for different borrowers and allowed some individuals to view others’ personal information, such as Social Security numbers, according to today’s Boston Globe.

The department said that the problem lasted only from Sunday night until Tuesday morning, with only “pretty limited” effect on the program’s 6.4 million borrowers, since not all of them use the online system. A spokesman said four borrowers had complained so far.

Software glitches are commonplace, and inadvertent disclosures of personal data have become increasingly frequent, but the combination of both gives a black eye to the direct-loan program, in which the federal government makes loans directly to students through their colleges, bypassing the banks and other lenders that make up the traditional guaranteed-loan program. The direct-loan program, created under President Bill Clinton, has long been a target of Congressional Republicans and the Bush administration.