CVE-2026-42336 — MaxKB: SSRF Bypass via DNS Rebinding in MaxKB OSS URL Fetch

MaxKB is an open-source AI assistant for enterprise. MaxKB 2.8.0 and prior are vulnerable to a server-side request forgery (SSRF) bypass in the OSS file service URL fetch functionality due to inconsistent DNS resolution between validation and actual request execution, allowing attackers to access internal network services. This vulnerability is fixed in 2.8.1.

Published May 26, 2026Updated May 27, 2026Sources: cvelistV5, GitHub_M

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the scoring sources call it.

Exploitation

Unreported

no source claims exploitation

EPSS

chance of exploitation in 30 days

Affects

1panel dev

maxkb

CVSS base

5.1

MEDIUM

CISA SSVC assessment

Three decision points CISA publishes for the CVEs it assesses · SSVC 2.0.3. A stakeholder decision, not a severity score.

CISA

Exploitation

None

none · proof-of-concept · active

Automatable

can an attacker script all four kill-chain steps

Technical impact

Partial

partial · total control of the vulnerable component

Affected scope

The catalog records vendors and products as separate lists, not pairs, so which product belongs to which vendor is not something this page can say.

Vendors (1)

1panel dev

Products (1)

maxkb

Every base score collected

Sources score independently and disagree; each row says who scored it and under which version.

Score	Version	Severity	Expl.	Impact	Source
5.1	CVSS 4.0	MEDIUM	—	—	cvelistV5

Weakness & attack patterns

CWE-367
CWE-918

References

1 on the record

github.com/1Panel-dev/MaxKB/security/advisories/GHSA-6m4p-9wwc-4q5q
x_refsource_CONFIRM

Elsewhere on this site

1panel devevery CVE for this vendor
CWE-367other pages naming this weakness

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.