CVE-2026-77521
MaxKB: Prompt-injectable agent can lead to command execution
Description
MaxKB is an open-source AI assistant for enterprise. Prior to version 2.10.5-lts, assistants with a tool, MCP tool, skill, or sub-application use SandboxShellBackend, which exposes an execute shell tool without excluding it and omits execute from interrupt_on, so human approval is not required. Untrusted chat or ingested content can therefore cause command execution; source deployments with MAXKB_SANDBOX disabled run commands directly as the application user, while the official root container's string-based gosu wrapper allowed shell metacharacters to execute outside the intended sandbox. This issue is fixed in version 2.10.5-lts.
INFO
Published Date :
Sept. 21, 2026, 9:17 p.m.
Last Modified :
Sept. 21, 2026, 9:17 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | CRITICAL | [email protected] |
Solution
- Update MaxKB to version 2.10.5-lts.
- Ensure MAXKB_SANDBOX is configured securely.
- Review and sanitize all ingested content.
- Verify shell execution controls.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-77521.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-77521 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-77521
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-77521 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-77521 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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New CVE Received by [email protected]
Sep. 21, 2026
Action Type Old Value New Value Added Description MaxKB is an open-source AI assistant for enterprise. Prior to version 2.10.5-lts, assistants with a tool, MCP tool, skill, or sub-application use SandboxShellBackend, which exposes an execute shell tool without excluding it and omits execute from interrupt_on, so human approval is not required. Untrusted chat or ingested content can therefore cause command execution; source deployments with MAXKB_SANDBOX disabled run commands directly as the application user, while the official root container's string-based gosu wrapper allowed shell metacharacters to execute outside the intended sandbox. This issue is fixed in version 2.10.5-lts. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H Added CWE CWE-78 Added CWE CWE-749 Added CWE CWE-250 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/77xxx/CVE-2026-77521.json">CVE-2026-77521</a> Added Reference https://github.com/1Panel-dev/MaxKB/commit/594f50f2ea80a502d1c955371ba0438b277c30ea Added Reference https://github.com/1Panel-dev/MaxKB/releases/tag/v2.10.5-lts Added Reference https://github.com/1Panel-dev/MaxKB/security/advisories/GHSA-f36j-f34j-h3rx