Card-based banking services at three of Iran's largest lenders were taken offline for a second time on Tuesday, after a cyberattack that first struck on 14 June continued to disrupt operations. The state-owned Informatics Services Corporation (ISC) said it had suspended all card-related operations at Bank Melli, Bank Saderat and Bank Tejarat to prevent unauthorised access and protect customer data. The move disabled ATMs, point-of-sale terminals and mobile banking apps for millions of account holders, and the resulting shift in transaction volumes caused intermittent slowdowns at other banks across the country.

The attack targeted a shared communications infrastructure managed by ISC, which also underpins the national Shetab and Shaparak payment networks. This concentration of critical systems in a single entity created a common point of failure, amplifying the disruption. A member of parliament's economic committee, Meysam Zohourian, told Iranian media after an emergency meeting with the economy minister and central bank governor that the source of the main attack remained unidentified and that even replacing hardware had not resolved the problem. He described the incident as more than a simple technical fault and estimated full restoration of digital systems could take at least two more weeks.

Iranian officials have not publicly attributed the attack, though authorities have previously blamed Israel for similar incidents, including a 2024 breach of Bank Sepah claimed by a group calling itself Predatory Sparrow. Israeli media, noting the timing, pointed to the United States' recent moves to unfreeze Iranian assets and allow oil sales, and speculated that a foreign actor was behind the operation. The central bank has denied reports that the disruption was deliberately engineered to control currency and gold markets, and insisted that customer data had not been compromised, though no independent technical report has been released to verify that claim.

By Tuesday evening, ISC announced that Bank Tejarat's card services had been restored, and the central bank said disruptions at other lenders had been resolved, predicting that the remaining outages at Bank Melli and Bank Saderat would be fixed by the end of the night. The communications minister separately ordered telecom operators not to cut off subscribers for unpaid bills while banking systems remain unstable, a measure aimed at containing public frustration. The next factual milestone to watch is whether the three banks regain full functionality within the central bank's stated deadline, and whether any official attribution or retaliatory statement emerges from Tehran.