US intelligence officials have told the Wall Street Journal that Russian President Vladimir Putin could try to test NATO‘s resolve with a limited attack on an allied country as early as this fall.

The assessment, first reported August 6 and expanded on by CNN a day later, lays out several possible scenarios. They range from a cyberattack to a small-scale incursion meant to challenge NATO’s commitment to Article 5, the alliance’s mutual defense clause.

Officials cited in the reporting say Ukrainian strikes on Russian energy infrastructure, combined with limited Russian gains on the battlefield after more than three years of war, could push Putin toward a different kind of confrontation, one aimed at NATO unity rather than Ukrainian territory.

The warning is not the first of its kind. In June, Germany’s top military officer, Lieutenant General Christian Freuding, told reporters that Russia could have the capability to strike a NATO member within three years, a timeline that has been shrinking in successive assessments from European defense officials.

None of this means an attack is imminent or confirmed. Intelligence assessments describe a range of outcomes rather than a single predicted event, and both the Pentagon and NATO headquarters in Brussels have not issued public statements responding directly to the Journal’s report.

Still, the timing matters. NATO members have spent the past year raising defense budgets and rotating additional troops through eastern member states, partly in response to exactly this kind of warning. Whether the alliance’s current posture is enough to deter a limited test remains the open question hanging over the assessment.

Analysts who track Russian military behavior note that Moscow has previously used cyber intrusions and airspace violations to probe NATO responses without triggering a full Article 5 crisis, and a similar approach appears to be what worries US officials most heading into the fall.