0
Jun 10, 2026
Slack AI could be tricked into leaking private-channel data via indirect prompt injection
PromptArmor disclosed in August 2024 that Slack AI could be manipulated through indirect prompt injection: an attacker posting in any public channel could plant instructions that, when a victim later queried Slack AI, caused it to render a markdown link exfiltrating private-channel content (such as secrets or API keys) to the attacker's server via the URL — without the attacker ever accessing the private data directly. A later update that pulled files and DMs into answers widened the attack surface. Slack deployed a patch.