CVE catalog
CVE-2026-39418
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 authentica
- Severity
- Medium · CVSS 5
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L - Published
- Source
- [NVD] · [CVE record]
- EPSS
- 0.20% · Oct 25, 2026
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.
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Cpe | maxkb | Not reported | 2.8.0 | fixed |
| Cpe | maxkb | Not reported | 2.8.0 | fixed |
Fixed-version evidence
| Distribution | Package | Type | Release | Fixed version | Urgency | Origin | Bugs |
|---|---|---|---|---|---|---|---|
| Cpe | maxkb | cpe | Not reported | 2.8.0 | Not reported | Not reported | Not reported |
| Cpe | maxkb | cpe | Not reported | 2.8.0 | Not reported | NVD-CVE-2026-39418 | Not reported |
OpenFactory catalog packages
No matching packages in this catalog.
Observed: