CVE-2026-42335 MaxKB: SSRF Bypass in MaxKB OSS URL Fetch due to URL Parsing Discrepancy
Attackers can bypass URL validation to access internal network services via the OSS file service endpoint in MaxKB.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-42335?
CVE-2026-42335 is a medium-severity server-side request forgery vulnerability in 1Panel-dev MaxKB, published on 26 May 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
MaxKB is an open-source AI assistant for enterprise. Prior to 2.8.1, MaxKB v2.8.0 and prior are vulnerable to a server-side request forgery (SSRF) bypass in the OSS file service URL fetch (chat/api/oss/get_url) endpoint. The vulnerability exists due to inconsistent URL parsing between the urlparse validation function and the requests HTTP client, allowing attackers to access internal network services. This vulnerability is fixed in 2.8.1.
Weakness: CWE-918
Which versions are affected by CVE-2026-42335?
How do I fix CVE-2026-42335?
No fix has been published for CVE-2026-42335 yet. Limit exposure of the affected software until one is available.
Upgrade, and send outbound requests through an allow-list that blocks internal addresses. More about Server-side request forgery.
Is CVE-2026-42335 being exploited?
There is no known exploitation of CVE-2026-42335 in the wild and no public exploit code.
Sources
Also known as GHSA-r8hf-mwwr-hxgc.