A security researcher was awarded a $1,750 bug bounty reward for discovering a remote code execution vulnerability in the Slack desktop applications.
An attacker could exploit the vulnerability to execute arbitrary code within Slack’s desktop apps for macOS, Linux, and Windows.
The issue was discovered by security engineer Oskars Vegeris of Evolution Gaming, who reported it in January 2020 via the company’s bug bounty program on HackerOne.
“With any in-app redirect - logic/open redirect, HTML or JavaScript injection - it's possible to execute arbitrary code within Slack desktop apps. This report demonstrates a specifically crafted exploit consisting of an HTML injection, security control bypass and a RCE JavaScript payload,” the researcher explained.
Vegeris notes that an attacker looking to exploit the flaw would need to upload on their server a file containing the RCE payload, then create a Slack post that contains HTML injection code and post that to a channel or send it to a specific user, to achieve one-click remote code execution.
Once the payload is triggered, the attacker gains access to private conversations and files on Slack, as well as to private files on the system, private keys, passwords, secrets, internal network access, and more.
Furthermore, the payload could be designed to be wormable, meaning that it would be automatically re-posted to all user workspaces after click.
In addition to this vulnerability, the researcher identified a Cross-Site Scripting (XSS) flaw in files.slack.com that could lead to arbitrary HTML content being displayed in *.slack.com and phishing attacks via fake HTML login pages, but which could also be abused to store the RCE exploit.
Details on the security bug became public ..
Support the originator by clicking the read the rest link below.
