Bank of America adds 1,000 contractors to repair bugs found by Mythos

In 2026, Bank of America added 1,000 contractors to repair the bugs that Claude Mythos found in its systems. Brian Moynihan, the chief executive of the company, told CNBC this. The contractors work with a security team of 3,000 persons. Anthropic made Mythos. It approved the company to use Mythos on its code.

What changed

Moynihan told Bloomberg that the work and its speed change. Banks must repair bugs more quickly.

Reports show that the time to repair a bug went from weeks to days.

What Mythos found

Anthropic released Mythos in April. At first, only a small group of organizations had access to it.

In tests, Mythos found thousands of zero-day bugs. 2 examples:

• A bug in OpenBSD that no person found for 27 years.
• A bug in the video library FFmpeg that automated tests did not find.

Most bugs in the banks were low or moderate in severity.

The wider reaction

Scott Bessent and Jerome Powell asked the chief executives of large banks to a meeting about the risk.

Anthropic has since stopped the use of Mythos by more organizations. Reports give 2 causes: a leak of some of the code, and access through a vendor that was not approved.

What is not known

Anthropic will give banks in the UK access. The source does not show the effect of this on the problem.