AT&T's stock at last check was down 2.7% to $27.68 after Cowen & Co. analyst Colby Synesael cut his rating.
Citing the growing threat of the coronavirus to the Dallas telecom giant's bottom line, Synesael also slashed his price target on AT&T to $37 a share from $43, according to Bloomberg.
The company's Warner Media unit is vulnerable during the virus-driven economic downturn, with HBO Max particularly exposed, the analyst wrote.
As a result, Cowen's Synesael lowered his estimates for Warner's bottom line based on the assumption that social-distancing measures will remain in place until at least June and the economy will be mired in a recession for the rest of 2020.
The Cowen analyst also pointed to the recent selloff in the telecom giant's stock as derailing the company's efforts to meet its three-year targets.
In the month through Friday, AT&T shares dropped more than $10, or 26%.
The telecom company also compares unfavorably in the current business climate with competitor Verizon (VZ) - Get Report. AT&T's more wide-ranging business empire creates "incremental uncertainty relative to more simplistic companies such as Verizon," the Cowen analyst wrote.
Analysts at Baird also downgraded AT&T on Monday, slashing their rating to neutral from outperform and their price target to $33 a share from $41.