MaxKB: Chat share-link endpoint missing owner check: a chat token can publish another user's conversation

published 2026-09-02 2mo ago modified 2026-09-22 last mo. also EUVD-2026-84158 , GHSA-m8gr-554p-8r82

Unreviewed: the maintainers' own advisory

Published by the maintainers on their GitHub repository 1Panel-dev/MaxKB. GitHub has not reviewed it into the GitHub Advisory Database, so the affected packages and versions are the maintainers' word. Read the full advisory on GitHub.

cvss: 6.5; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 19%
public exploits: 0; none known

MaxKB is an open-source AI assistant for enterprise. In 2.7.0 through 2.10.4-lts, POST /chat/api/{application_id}/chat/{chat_id}/share_chat verifies that a conversation exists but does not verify that it belongs to the authenticated chat_user_id or to the application bound to the caller's token. An attacker with any chat token and a known victim chat_id can create an unauthenticated public ChatShareLink exposing the victim's conversation and can create PublicFileAccess state that makes associated files retrievable without credentials, with no available revoke path. No fixed version is available as of this review.

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CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: last mo. (2026-09-22)

Exploit prediction

0.27% chance of exploitation in the next 30 days, higher than 19% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by	version	score	vector
CNA	3.1	6.5	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N

Affected products

1Panel-dev MaxKB

Classification

Weakness

CWE-285 Improper Authorization
CWE-639 Authorization Bypass Through User-Controlled Key

References

github.com /1Panel-dev/MaxKB/security/advisories/GHSA-m8gr-554p-8r82
advisory

Sources

CVE List CVE-2026-79917
NVD CVE-2026-79917
Maintainer advisory GHSA-m8gr-554p-8r82

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

The maintainers of 1Panel-dev/MaxKB published their own advisory on GitHub. Reviewed sources take precedence over it.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.