vantern-org questbot up to 1.1.8 Request Helper dns rebinding

Summaryinfo

A vulnerability, which was classified as problematic, has been found in vantern-org questbot up to 1.1.8. This affects an unknown function of the component Request Helper. This manipulation causes dns rebinding. This vulnerability appears as CVE-2026-61840. The attack may be initiated remotely. There is no available exploit. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic was found in vantern-org questbot up to 1.1.8. Affected by this vulnerability is an unknown functionality of the component Request Helper. The manipulation with an unknown input leads to a dns rebinding vulnerability. The CWE definition for the vulnerability is CWE-350. The product performs reverse DNS resolution on an IP address to obtain the hostname and make a security decision, but it does not properly ensure that the IP address is truly associated with the hostname. As an impact it is known to affect confidentiality. The summary by CVE is:

Quest Bot is an opensource Discord Bot. Prior to 1.1.9, the `image to GIF` command uses a request helper that validates a hostname's public IP addresses but then sends the actual request by hostname, causing a `second DNS lookup`. An attacker controlling a domain can return a public address during validation and an internal address during the connection, bypassing the internal-address protection through `DNS rebinding`. The command takes its address directly from user input and its developer-only gate is disabled in normal deployments, so any member of a server with the bot can trigger the flaw without special permissions. Requests are restricted to `HTTPS on port 443`, and content is returned only when the response is a `genuine image`. The impact is therefore mostly blind internal probing with limited retrieval of image responses from loopback or internal endpoints, not arbitrary internal-data disclosure. Common cloud metadata services using plain HTTP on another port are not reachable through this path. This issue is fixed in version 1.1.9.

It is possible to read the advisory at github.com. This vulnerability is known as CVE-2026-61840 since 07/10/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1583.002 according to MITRE ATT&CK.

Upgrading to version 1.1.9 eliminates this vulnerability.

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Productinfo

Vendor

• vantern-org

Name

• questbot

Version

• 1.1.0
• 1.1.1
• 1.1.2
• 1.1.3
• 1.1.4
• 1.1.5
• 1.1.6
• 1.1.7
• 1.1.8

Website

• Product: https://github.com/vantern-org/questbot/

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