CVE-2026-35661: OpenClaw authorization bypass in Telegram callback query handling

Executive brief

OpenClaw is a library used for building Telegram bots. A vulnerability in how it handles direct message (DM) interactions allows unauthorized users to bypass pairing requirements and modify session data. This could allow an attacker to interfere with bot operations or manipulate user session states without proper authorization.

Technical details

OpenClaw versions up to 2026.3.24 contain an authorization bypass vulnerability (CWE-285/CWE-288) in the handling of Telegram callback queries. Specifically, inline button callbacks from direct messages utilized a weaker, callback-only authorization mechanism that did not verify if the user had satisfied the required DM pairing. This allows a remote attacker to send callback queries that mutate session state without proper authorization. The issue was addressed in version 2026.3.25 (and later 2026.3.28) by enforcing full DM authorization for all callback queries.

Affected products

• openclaw openclaw <= 2026.3.24

Timeline

• 2026-03-26: disclosed
• 2026-03-29: advisory: GitHub Advisory published
• 2026-04-10: other: NVD published CVE-2026-35661

References

• https://api.github.com/users/zpbrent
• https://github.com/zpbrent
• https://api.github.com/users/zpbrent/gists%7B/gist_id%7D
• https://api.github.com/users/zpbrent/repos
• https://avatars.githubusercontent.com/u/834641?v=4
• https://api.github.com/users/zpbrent/events%7B/privacy%7D