# CVE-2026-42335: 1Panel-dev MaxKB SSRF in OSS file service URL fetch

Source: https://junglewise.ai/threats/cve-2026-42335-1panel-dev-maxkb-ssrf-in-oss-file-service-url-fetch  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-05-26. Updated: 2026-05-26  
License: CC BY 4.0 with a link back

CVE-2026-42335 · Severity: info · CVSS 6.3 · Published 2026-05-26

MaxKB is an open-source AI assistant used by enterprises to build knowledge bases and chat interfaces. A security flaw allows logged-in users to trick the system into making unauthorized network requests to internal servers that should be private. This could allow an attacker to probe internal infrastructure or access sensitive internal services that are not exposed to the internet.

Technologies: [1Panel-dev MaxKB](https://junglewise.ai/threats/technologies/maxkb). Vendors: [1Panel-dev](https://junglewise.ai/threats/vendors/1panel-dev).

## Quick answers

**Is CVE-2026-42335 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-42335 being exploited in the wild.

**How severe is CVE-2026-42335?** Informational severity, with a CVSS score of 6.3, published 26 May 2026.

**Which products and versions are affected?** 1Panel-dev MaxKB <= 2.8.0.

**Is there a fix for CVE-2026-42335?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-42335 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-42335?** Check whether you run 1Panel-dev MaxKB at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A Server-Side Request Forgery (SSRF) vulnerability exists in the /chat/api/oss/get_url endpoint due to a URL parsing discrepancy. The application uses Python's 'urlparse' for validation but the 'requests' library for the actual HTTP call. An attacker can provide a malformed URL (e.g., using backslashes and @ symbols) that 'urlparse' interprets as a safe external host while 'requests' interprets as an internal IP address. This allows authenticated attackers to bypass security filters and reach internal network services. The issue is resolved in version 2.8.1 by unifying the parsing logic.

## Affected products

- 1Panel-dev MaxKB <= 2.8.0

## Timeline

- 2026-05-06: advisory: GitHub Security Advisory published
- 2026-05-26: disclosed: CVE published to NVD

## References

- [https://github.com/1Panel-dev/MaxKB/security/advisories/GHSA-r8hf-mwwr-hxgc](https://github.com/1Panel-dev/MaxKB/security/advisories/GHSA-r8hf-mwwr-hxgc)

## Related threats

- [MaxKB chat-record routes authorization bypass in management API](https://junglewise.ai/threats/cve-2026-77525-maxkb-is-an-open-source-ai-assistant-for-enterprise-in-2-10-2-lts)
- [MaxKB cross-workspace model parameter form write](https://junglewise.ai/threats/cve-2026-77523-maxkb-is-an-open-source-ai-assistant-for-enterprise-in-version-2)
- [MaxKB knowledge web-document crawler server-side request forgery](https://junglewise.ai/threats/cve-2026-77522-maxkb-is-an-open-source-ai-assistant-for-enterprise-in-version-2)
- [MaxKB command execution in SandboxShellBackend](https://junglewise.ai/threats/cve-2026-77521-maxkb-is-an-open-source-ai-assistant-for-enterprise-prior-to)
- [MaxKB authorization bypass in application discovery and invocation](https://junglewise.ai/threats/cve-2026-77520-maxkb-is-an-open-source-ai-assistant-for-enterprise-in-2-10-2-lts)