Description
MaxKB is an open-source AI assistant for enterprise. In versions 2.7.1 and below, sandbox network protection can be bypassed by using socket.sendto() with the MSG_FASTOPEN flag. This allows authenticated user with tool-editing permissions to reach internal services that are explicitly blocked by the sandbox's banned hosts configuration. MaxKB's sandbox uses LD_PRELOAD to hook the connect() function and block connections to banned IPs, but Linux's sendto() with the MSG_FASTOPEN flag can establish TCP connections directly through the kernel without ever calling connect(), completely bypassing the IP validation. Although sendto is listed in the syscall() wrapper, this is ineffective because glibc invokes the kernel syscall directly rather than routing through the hooked syscall() function. This issue has been fixed in version 2.8.0.
INFO
Published Date :
2026-04-14T00:08:50.182Z
Last Modified :
2026-04-14T15:54:30.206Z
Source :
GitHub_M
AFFECTED PRODUCTS
The following products are affected by CVE-2026-39418 vulnerability.
| Vendors | Products |
|---|---|
| 1panel |
|
| Maxkb |
|
REFERENCES
Here, you will find a curated list of external links that provide in-depth information to CVE-2026-39418.
